BUT I am also a beginner and I'm speaking from the little experience I have
and im sorry for the 4 post notification blast you are about to have

Also for visual novels its okay to not draw any CGs and have your sprites express everything you want them to. Nadia's own website has a lot of info and resources for anything else you can't do on your own (BGs, OST, SFX, and so on)

Don't be shy from tracing if you're still learning (I don't know if I can recommend tracing other people's art for a game). 3D puppets are great for using as a skeleton, there are some websites where you can utilize them. It also helps to break down and study the process of drawing and rendering.

Practice makes perfect! Don't worry about your art style coming off as crude and amateurish, you can't get better at drawing without drawing in the first place. Also the page states how "good" your drawings are doesn't matter, as long as you put your heart into the entire thing

can i keep the collar after i have made my submission or do they just vanish