There’s a book on Amazon that is like the fabric bible but I believe it’s crazy expensive.
I’ll be honest, there’s a lot to learn. The best way is to just buy swatches, go to your local fabric store and investigate. Touch, feel, understand.
Over time you’ll learn what you like and what you don’t like and you’ll learn all about the fibres but just take it slow, don’t try to learn everything at once, and have fun!
I found mine on Amazon: https://www.amazon.com/dp/1780672330/ref=cm_sw_r_cp_apa_i_C6asFbMJAJBK6
There really is a market for a good selection of fabric samples from one source. I don't know of one. Dharma Trading Company offers 4 inch swatches, you wouldn't need all of them. They are nice because they are mostly undyed so the focus is on the fabric, not prints or colors. Vogue Fabrics has swatch catalogs and a buyers club where they send out swatches, there is a fee to join but there are usually discounts to offset the cost if you order the fabric. Fabric Mart has a similar program, Julie's Pick's Club. Spoonflower offers a sample pack for $7 of their fabric bases.
Fashion students use The Fabric Swatch book, there is a new edition coming out soon according to Amazon. It's pricey and the reviews are mixed.
It's probably best to narrow down your focus to the type of sewing you'd like to do and go from there as all of these sources have a particular audience, you know?
To touch a variety of fabrics, you can definitely go to Jo-ann's, and just walk around touching fabrics. They have a decent selection, and while it's not the highest quality out there, it's affordable. You can buy fabrics in amounts as small as 1/4 yard. Just take the bolt of fabric you like to the cutting table (located in the fabric department) and tell them how much you want. They'll cut it for you. If you go there and find fabric you like, that's probably your easiest option.
There are also many places online you can buy fabric, like https://www.fabric.com/ I'm not sure if you can buy smaller than 1 yard quantitites there. Fabric.com will let you buy swatches (an 8" by 8" piece) of some of their fabrics (info here). Another reputable online shop is Mood fabrics.
You can call either of those stores, and you should be able to chat with someone, tell them what you're looking for, and then be able to order a few swatches. Since you only need an 8" by 8" piece of fabric for the tutorial, if you find a swatch you like, it should be enough. (Not sure how big Mood's swatches are though.)
Finally, there does exist big books of fabric swatches, like this one, but they're not cheap, and probably more than you're looking for at the moment. But I thought I'd mention its existence anyway.
HTH
I'm considering saving up for Fabric for Fashion: The Swatch Book. So pricey, but so neat! >_<
Edit: link!