we can get above 75 for 80 plzz tell me

Yes, if you study well from NCERT books ant practice the questions well, you surely can

what preparation tips and suggestions woyld u like to give me when u where in 10 how did u succed and hw much was ur CGPA PLZZ dont mind im asking to score well in my xams

Jaya,the some tips that I would recommend would be to read the NCERT books thoroughly and not skip even one line. For Maths,try and practice as many questions as you can and from as many sources possible. After preparing,do previous year question papers and get them checked by your teachers as they would be able to point out your mistakes. The last tip would be to remain confident and not panic on the day of the exam.
As for my performance, I passed class 12th from ICSE board with 96.5% marks.

And class 10th too from ICSE board with 96.4% marks