None. If you can write, you can be a writer. You may not be any good at it and hence be a starving writer, but there's no actual requirement that you go to college (and no guarantee that going to college will help all that much anyway).
Enough to at least spell college
It depends on how great you want to be because it takes long years to gain thinking skills to be a science writer=•=
You need 7 years of college.
5-7 years
nurses have 2 years of college
you need to go to college for 2 years
Models do not need college for their job.
2-4 years of college
3.4 years
8 to 10 years
You do not need to go to college to be a beekeeper. Many people do it as a hobby.
i would say about 4 years of college