Yes-usually you don't need to be perfect but you do need to have a decent gpa (the school will have decided on this gpa in advance) and be eligible to play in both high school and College Sports.
Go to college
football in college
Softball
Varsity Athletics.
Football
Tennisp
No because you have to get drafted from college. Actually - you can't because once you get paid, you cannot play for the NCAA - this applies for NCAA colleges only...I assume.
football.
Volleyball
yes you can
Baseball
Yes. There is no rule against it.