suggest me some government college for btech in biotechnology which a PCB can opt without having maths in 12
Unfortunately, maths is one of the compulsory subjects you need in 10+2, if you want to do Btech irrespective of any brach. Technology cannot be studied without maths.
Although if you're genuinely interested in biotechnology you can go for B.Sc in biotechnology or diploma, these courses just need the candidate to have passed class 12th with science stream, with or without maths.
All the best!