Are we not allowed to program games that have Nintendo Characters or something?

Nintendo owns those characters and of you do post a game with their characters in it, it can be deleted because of copyright issues. It's a bummer, but it's reality

Dinga danga darn it! now i have to change the characters!

You should be able to use the characters as long as you say they don't belong to you, but to Nintendo, I think. As long as your project isn't a blatant copy of any of their games, it should fall under fair use as a parody work.

IDK about that one too, someone tried to create a FNaF game and he said in the game that the characters don't belong to him, but that was deleted because of copyright issues

It will probably get taken down if you publish it, just be warned, hylain's fnaf sb did...