GCSE French predicted 9, should I proceed to DELF B1 and/or B2?

My current French teacher has encouraged me to pursue further qualifications in French after my predicted and mock grade for GCSE French turned out to be 9.

I have been studying French at Alliance Française from the start of year 7 until spring year 9 (~11 courses inc. 1 fast track), and have already done the A1 Junior qualification (and supposed to do A2 in summer year 9 but I left).

I have since moved to the UK and in my mocks for GCSE French I got marks of 30/50(Listening) 55/60(Speaking) 57/60(Reading) 54/60(Writing)

I'm just not sure where B1 and B2 sit and how much work would be required in my 2 years of sixth form to achieve those qualifications. I would be doing 4 subjects (Maths[already self-studied all content of AS] AddMaths Physics Chemistry) in addition to my Native Language (sorry for that school wouldn't pay for IGCSE first language) alongside commitments for Piano ATCL and Grade 8 Music Theory.

On a related note, how do A-Level French and DELF B2 compare?

Thank you for any response!