B.Sc

If you have a good percentage in class 12th then you can go for direct admission in many government colleges like DU where the fee is low and importance of govt. degree is more than a private degree.

Sorry to inform you, but no. For M.Tech, either you should have a post graduation degree or undergraduate degree in a technical field that means B.Tech. You cannot go for M.Tech after B.Sc, however, some universities still offer M.Tech of 3-year duration after your B.Sc. Yes, some M.Tech courses can

Follow the link below and get the procedure:
https://www.shiksha.com/science/course/b-sc-in-physics-and-computer-science-sastra-university-thanjavur-284536

You can follow the link mentioned below for the answer:
https://www.google.co.in/amp/s/www.shiksha.com/science/articles/amp/top-10-bsc-msc-colleges-in-india-blogId-13473

Yes, you can do B.Sc in CS. You must score 50% aggregate and English as a subject to be deemed eligible.

Hey Dear,
You will have to qualify an admission test. Online forms would be available online by the end of January.
Eligibility criteria: Senior Secondary School Certificate or an equivalent examination with at least 55% in
aggregate of english, physics, chemistry and biology/mathematics.
For admission

Hey Dear,
There various options available for B.Sc Mathematics graduate to pursue their higher studies. Details of best higher studies options for B.Sc Mathematics graduates are given below.
M.Sc/Ph.D: One of the best higher studies option available for the B.Sc Mathematics graduate is to do Masters D

You can apply for the course but I suggest you to give auditions for the same.

Hello
Yes.
You can pursue M.Sc in EVS.