Users can not post

No one can post anything on the forums I've built. I think it has to do with chmod, anytime I change it I get "Internal Server Error". Same with when I try to deploy with PHPStorm, I get "Internal Server Error".

I really love the web panel and want to continue using it, is there any way to fix this issue?

go to user accounts >> fix permission >>> choose user from drop down menu >>> Hit fix permission

That doesn't fix the issue with users posting, I believe the issue with that is since it uses MySQL I need chmod 775 for the file? Also  internal happens everytime I deploy a file using PHPStorm.

Know any fix?

check the error log, this will help you a lot