Teaching & Education

You want to become a TGT maths teacher in DSSSB. So in my view, you will have to opt for Maths.
Apart from that, if you require any knowledge on DSSSB Syllabus. then you can catch up information on below post: http://bit.ly/dsssb-exam-pattern
Thanks and ask if you have any other query!

You already did Master's right? Then, why are you choosing again a Master's? If your question is mistaken as B.Sc, better do M.Sc physics and try to clear NET or SLET for lectureship.
B.Ed also took two years but, now a days, good government job with B.Ed is a little bit tough to get due to the TRB and TET problems.
Good percentage in M.Sc will give you scope in research further with financial support.

For B.Ed, if you are financially sound and not looking for jobs immediately, then go for PhD.

Yes, there is no problem but 2-degree courses done together at the same time have no value.

Please use the link provided below for an exhaustive list of colleges which offer B.Ed courses from Gujarat. You should be able to navigate to a college of your choice using the filters on the web page. Download their brochure for details regarding the institute, course eligibility, admissions etc.
https://www.shiksha.com/teaching-education/colleges/b-ed-colleges-gujarat

B.Ed and teaching experience are the necessities.