I am currently on a B2 visa for 6 months and have the opportunity to work in the U.S. after that 6 month period. Can I change my B2 visa to a J1. If so what do I have to do?

Yes, but you are only "changing" your visa status, as noted on your I-94, not your visa, laminated in your passport. Generally, the J-1 program administrator will have their attorney file with the USCIS service center for the change of status from B2 to J-1.

You will need your passport, with visa, I-94, evidence of your qualifications for the position and the DS-2019 from the PA.

I trust this is responsive to your inquiry.