Quit college for cycling?

what cat. racer are you? Are you currently racing?

I'm not looking to piss on your chips but if you're not currently racing you've left it very, very late to pursue a road racing career - there will have been kids in clubs and development squads since their very early teens

get qualified, earn money, enjoy your racing

don't anticipate that you will make any money, at all, from road racing

A good deal of this is true, but if the OP is really serious about racing there is no reason why he can't train hard and do the degree at the same time. The kids with potential that I know of in London do that and it doesn't stop them competing at a national and international level.

What the OP really needs is a clear plan of how to get involved in racing:

1. Are you in a club?
   
2. Do you have a training plan or schedule?
   
3. Do you have access to coaching?
   
4. Have you entered or do you plan to enter races?
   
   

Look at resources online and see if you can find blogs by promising juniors to understand what they put into cycling and how they balance it with other aspects of their lives. Then you will have a realistic framework for your ambition.

Whilst you may have left it late compared to most of your contemporaries, you are young enough to find out if you have a genuine talent if you apply yourself seriously.