Potentially buying my first bike. Looking for advice, possibly recommendations

Hi, I have recently passed my CBT and my theory is booked for the 20th. I will be doing my unrestricted licence in one go but still need to Try and save up before I do but the thing is my commute would benefit massively from having a bike now. The school I went with does direct access, tests and lessons, for 950 over 3 full days. Is it good value, should I wait till I get my full licence, and can anyone recommend any good 2nd hand bikes / dealers around Yorkshire?