If you can find the America’s Test Kitchen Book, it has a section of gluten free cookies. I have not tried it but the rest do their recipes have been great. The Perfect Cookie: Your Ultimate Guide to Foolproof Cookies, Brownies & Bars (Perfect Baking Cookbooks) https://www.amazon.com/dp/1940352959/ref=cm_sw_r_cp_api_i_PQVBY1NYZSQXTWDA1967
Baking is my absolute favorite. I've been teaching myself from books for nearly twenty years now. My first suggestion is to find a well-reviewed book of recipes of the kinds of things you want to bake. When I'm checking out a new recipe/cookbook, I read reviews to see if the high ratings come from people who share my preferences in baking. Baking can be time-consuming. If I'm going to take the time and ingest the calories, I want the finished product to be fantastic, not okay.
I'm a big fan of America's Test Kitchen/Cook's Illustrated. Sometimes their recipes are a bit fiddly, but if you follow the directions, you're going to have success. And I love that they explain why the recipe contains certain steps or ingredients. They're a great resource for learning more about food science. Their The Perfect Cookie and The Perfect Cake books are awesome. Serious Eats also takes a great, scientific approach to cooking and baking. (Any recipe that includes a "why it works" section is a great resource for beginners.) I also love Fine Cooking and Bake from Scratch for high-quality recipes (they do have some beginner-friendly recipes; they do also have some harder things that are good once you've got more experience).
Next up, see what skills or equipment you need. For the kind of baking I do, a scale, a stand mixer, a whisk, a digital thermometer, an oven thermometer, and a mesh strainer are essential. (That said, a stand mixer is a big investment. As long as you're not making really stiff/thick doughs or candies, a hand mixer will do fine and cost much less.) Having the right kind of pan for what you're baking will help it bake properly. Parchment paper is your friend. It makes cleanup easy and, after you grease a pan, adding parchment and greasing it, too, makes for much easier, cleaner release of cakes and brownies.
Read your recipe thoroughly before you start. Make sure you have all your ingredients and have time for all the steps (no surprises if one of the steps is "chill for two hours"). Know how to check when your baked goods are finished. Some cookies need to look slightly damp when they come out. Many cakes should pass the toothpick test (only a few crumbs on a toothpick inserted in the middle).
Know how to measure. If your recipe calls for weighing ingredients, get a scale and use it. It's a wonderfully accurate way to measure. If you're measuring by volume, use dry measuring cups for dry ingredients and liquid measuring cups for liquids. They will produce different results. When you measure your dry ingredients, use the dip-and-sweep method, as most food sciencey bakers consider it the most accurate way to measure by volume. It's exactly what it sounds like: dip your measuring cup into the dry ingredient and scoop. Your measuring cup should have excess on the top. Use flat object (like the back of a knife) to sweep off the excess and make it level. Don't pack your ingredients in (unless you're measuring brown sugar).
Familiarize yourself with baking basics. Learn how to cream and why. Get in the habit of mixing your dry ingredients before adding them. Learn what it looks like to leave some lumps in batters that shouldn't be overmixed (quick breads, muffins, some pancakes). Learn how to cream (and later, how to reverse cream). Know when to take the time to sift and when you can skip it (for cakes that are supposed to be lighter and finer, always sift the flour, for regular cakes, I usually skip it; when using cocoa, always sift because it tends to clump). Practice cracking eggs, separating eggs, and whipping egg whites. Eggs are easiest to separate when cold. Make sure your equipment is clean and no fat (including egg yolk) gets in the whites when you're whipping. Learn what soft and stiff peaks look like in eggs whites and whipped cream and how to identify when you're on the verge of overbeating. If needed, learn how to proof yeast and how to feel when the liquid you're activating your yeast with is hot enough to provide good growth without being so hot it will kill the yeast. I find melting chocolate easiest in the microwave, working in short bursts with regular stirring.
Get familiar with common baking ingredients. Most baking calls for unsalted butter, large eggs, and full-fat milk. If your recipe calls for a specific kind of flour, salt, or sugar, use it. Pay attention to how different versions of the same ingredient behave. Oils make cakes have a moist mouthfeel; butter has a drier feel in cakes but a rich flavor. Shortening can provide a nice structure in bake goods that are hard to work with or tend to spread; however, sometimes the mouthfeel or flavor are less desirable. Cake flours are low-protein for soft and tender baked goods. Bread flours are high-protein and help develop a great structure. The use of potato flour can make rolls moister. Rice flour can make shortbreads more tender. Don't be put off by unusual ingredients when you have the time to look for them--many of them are easier to find and use and less expensive than you might think, and they can open up new flavors or new techniques.
Learn to recognize when it's worth spending extra on ingredients and when it's not. Your recipe is only going to taste as good as the starting ingredients. That said, we don't all have the palates of supertasters, and we'll each have ingredients where we can't tell the difference between top-dollar and generic. I always buy good-quality chocolate and vanilla, and switch between great butter and middle-grade butter. Really good chocolate and butter can make the difference between a good cake and something that tastes like you bought it at a high-end bakery.
In the beginning, don't make substitutions or changes. First, learn how the recipe behaves as you practice making it 100% according to the directions. This will give you a foundation for understanding the ingredients, their chemistry together, and the way they're affected by how you mix them and bake them. As you continue to bake, you'll learn more about different flours and sugars and techniques, and you'll gain an understanding that will let you recognize whether a recipe is going to work or not and how you can make your own alterations to it.
Don't be afraid to try something new. Caramel, marshmallows, laminated pastries, pate a choux, custards, and lemon curd all seemed terribly hard to me years ago. With practice and patience, they've all become easy.
And above all, be patient. A lot of baking is about spending a few extra minutes on precision or waiting for things to rest or chill or rise. Take the time to wait and you'll get better results. And be patient with yourself as you learn. There will be mistakes, and sometimes you'll have to throw things out, and that's just part of the process. When something goes wrong, re-read the recipe to check for mistakes, and research online or ask people you know who have experience if they can give you some tips. With time and patience, you can learn to do almost anything a chef in a professional kitchen can do.
So that's where I'd suggest you start. You know you love baking and sweets. Pick a couple of desserts that really excite you, find some highly rated recipes, and practice them. When you've got them down, expand to slightly more challenging recipes.
If you've got something specific in mind and would like some suggestions for finding good recipes, I'd be happy to point you toward sources or recipes I've found reliable. And if you'd ever like troubleshooting help or just want to talk about baking, you're welcome to hit me up! As you can see, it's a passion of mine. And I love helping people learn about it.