The FAQ might be a good point to start:
https://www.newgrounds.com/wiki/frequently-asked-questions
If you have specific questions you cannot find the answer to, there is a dedicated sub-forum for questions:
https://www.newgrounds.com/bbs/forum/3
(Note that the kind of users who can answer your questions have also read the FAQ at some point and can tell when you're just being lazy...)
Osaka
Here's an outdated video, maybe it will help still! - https://www.youtube.com/watch?v=5X8QXet81l4
Also this - https://www.newgrounds.com/wiki
Welcome to Newgrounds!