Hi mate,
Basically any one can turn pro off any handicap! A 36 handicapper can turn pro if they want, theres nothign stopping them lol! Although that would just be stupid.
You can get on european tour by working up the smaller tours such as europro and challenge tour (come in top 20 of challenege tour and you get on european tour). But to go to Q-School you have to have a handicap of 4 or below (or be a pro). Once you tee off in Q-School you are now a professional golfer.
For nationwide tour its the same. there is a q-school and you have to be below 4 handicap to enter q-school, or turn pro and THEN play in q-school. You can find entry forms for q-school on
www.europeantour.com .