this book might help - https://smile.amazon.com/Mini-Habits-Smaller-Bigger-Results/dp/1494882272/ref=sr_1_3?ie=UTF8&qid=1522095169&sr=8-3&keywords=mini+habits. it's a short, easy read. you could probably get similar information via google or youtube if you search "how to build a habit" or something like that
You sound like you are overwhelming yourself with options which typically will cause paralysis in even the most focused individual. You need to start small and not worry about all the rest of the stuff (I know, easier said than done).
If you want to skim through another book, I would recommend mini habits, it is a quick read with a lot of obvious, yet insightful information on how to get the ball rolling. If you don't want to waste your time here is the gist... pick two or three things you want to face or deal with on a daily basis. Write down laughably easy tasks to do each day, for instance if you are afraid of going outside make your goal to be to walk to the end of your driveway each day (or even place your foot out the front door). If you do more than this, that is good too, but if you only manage to do this easy task it is still a victory. Celebrate these victories, and recognize that you have done these small habits every day now for two days, five days, a month, etc. This will passively build a subtle confidence in your brain that says 'all I need to do is x, and x is easy.' Adjust these habits accordingly, and make sure to never increase the difficulty to a level that you could not complete even if the daily grind is against you. Slowly, you will add more habits and 'finish' others, making your victories even sweeter. Feel free to PM me if you have questions, but hopefully this should get the ball rolling for you :)
Read "Mini Habits." Use the advice given and it'll change your life. https://www.amazon.com/dp/1494882272/ref=cm_sw_r_sms_awdb_t1_Ac92Ab97CJR7E