What are some ways you can get denied from a university?

I am a high school senior applying for USF but I'm afraid i will get denied. I took the SAT and its in my application but the score is HORRIBLE!!! I just want to make sure if i apply i wont get denied; I would much rather get differed than denied. And i am taking the ACT and SAT both about two more times. Please i need your help and reurance!