Studying in the US

Hi, so I am a 20f au pair in America and I am interested in becoming a full time student at a university. I know that I need to show that I am financially capable. But I am more focused on how the process will work and how to go forward. My visa doesn’t require me to go home for 2 years and I have around 5 months left of my stay and I am planning on extending. So any advice or suggestions on how to do this, that will be helpful.