It doesn't work like that. If your high school grades are bad then you still might be able to get into a college, but the college might try to challenge you to see if you actually deserve a spot.
I was challenged by the first college that I attended, and I beat their challenge, so I earned a spot, and I also got a loan as well to pay, for my college tuition.
Unfortunately I didn't graduate from the second, and third colleges that I attended. I ended up dropping out, but I did graduate from the first college I attended.
If I remember correctly all three of the colleges that I attended accepted me. The process, for me to attend the second, and third college was different than the first college.
Lastly I think your parents can pay, for you to go to college, but you are probably going to have to somehow prove that you deserve a spot.