It depends what you are thinking about studying at university, and/or if you have any idea what you want to do after uni.
You will have to apply to unis and courses that accept a BTEC, while most courses require 3 A-levels, there are various courses out there that accept BTEC. If you look on the general entry requirements page for the uni it will say if they accept BTEC or not, you can then look further to see which courses they accept BTEC for.