Drawing realistically is something I still struggle with, but I'll try to help ya out. I'll link some tutorials that helped me.

Don't be afraid to use photos and videos as references, but don't just copy what you see. Try to learn from the references you use so you can become less reliant on them in time. I do that when I'm drawing animals I've never drawn before; I try to memorize how their body looks and how things are proportioned so I don't have to keep looking at reference photos of them each time I want to draw them.

I hope these tutorials help you out. c:

https://design.tutsplus.com/articles/human-anatomy-fundamentals-basic-body-proportions--vector-18254
https://design.tutsplus.com/tutorials/how-to-draw-fur--cms-27830
http://glitchedpuppet.deviantart.com/art/How-I-See-Color-A-Tutorial-184642625 (Long, but this is really informative. Probably one of the most in-depth tutorials I've seen for color theory)
http://palidoozy-art.tumblr.com/post/131593219986/more-info-under-cutmore-so-i-was-gonna-write
http://img15.deviantart.net/67fb/i/2012/182/9/8/tutorial__head_angles___perspective_by_rockinrobin-d55lt67.jpg
http://dersketchie.deviantart.com/art/Perspectives-Tutorial-328049480

Hey there ^.^ I just thought I'd stop by and offer this group to you! It's a group that I started, and serve as an administrator for (along with 2 others), to help all sorts of craftsmen and artists of all skill levels improve their crafts through advice, critique, redlining, anything and everything!

If you have telegram (it's free if you don't), we are mainly on there -> https://t.me/joinchat/DHR9Ag7vGfKag17UFLBDnw

If you don't have telegram, but would like to join, you can feel free to join our FA page as well! -> http://www.furaffinity.net/user/thecreativereview/