Hello,
In 11th there is not special physics group after 10th. There are PCM, PCB, PCMB that have physics as a subject in the course. With about a minimum of 75% helps you better in future for any courses in future. If you passed your 10th that is actually enough to get you to your 11th, but with atleast 75% gets you into decent 12th standard schools.
Good Luck!

You can score anywhere more than 60 percent marks as no one is going to ask your 10th marks if you are having a first division in future.Still for better and on safer side and also to get good knowledge you can score as much you want.The physics group you are asking is if some kind of coaching then please ask that coaching authorities for the criteria.

Hope this helps and feel free to ask.