My question is if I'm 19 years old and I leavy by myself in united states and I work part time, I have to pay rent,food,gas, staff I need and I want to go to college. How can I ask the government to help me without paying them later.

Actually you are more likely to find a scholarship (free education funds as opposed to a gov't loan) from a private source. There are so many that they are hard to find! My nephews are getting scholarships to go to college, but they are local to where they live. Start googling scholarships. There might be one for 'child of Korean War veteran who lives in San Diego' or something very obscure (I just made that up) so you have to keep looking. If you want help, ask us, but you need to give us all the details of your life.
You also have to have done well in high school.