What should you do? first, please read the rules of this forum. as a newbie i suggest you to read a lot in subforum beginners and help. there you will find a guide to get coins from this forum.
How many post? Well,activity only increases 14 every two weeks. so, the logic in a day to make one post is enough, which is important according to the rules that apply, not spam / junk. however, you can create more than one constructive post.