Iam an diploma student which exam Is needed to be write to continue betech from 2 ND year in banglore

Diploma student can also apply for JEE Main Entrance Exam but they can not take the admission on the basis of JEE Main Score, They need to qualify JEE Main to be eligible for JEE Advance. They can get admission in IITs only but in the first year of Engineering programme.

If you belong to Karnataka then you can apply for Karnataka DCET Entrance Exam which offer the admission direct into the second year of B.tech programme. You can check the eligibility to apply with the given below link.

http://kea.kar.nic.in/diploma_2018/diploma2018_brochure.pdf

Any particular college in Bangalore you wish to take the admission then let me know.

Good Luck!