CBSE

Yes Priyansh, you can. Additionally, check that you have some extracurricular activities too.

Read maximum Hindu or Indian express newspaper every day. Also, practice hearing English channels like CNN, BBC etc. Also, start reading blogs related to subjects of interest. These are some of the methods, which you can use.

You can try to get admission as your marks are quite good, so there are some chances of getting a seat in TCE-Madurai. So, you can try to get admission, you may get admission there.
Good luck.

Yes, you can get it. You can apply for management seats in private colleges like Amrita, Amity, PES, etc.

You may check on these institutes like Institute of Technology, Guru Ghasidas Vishwavidyalaya (A Central University), Sant Longowal Institute of Engineering and Technology, Longowal, Shri Mata Vaishno Devi University, Katra and HNB Garhwal University, Srinagar.
As you are expecting a good percentage in 12th, you have good chances of getting top branches.

As last date for the PU is May 30, CBSE will announce results between May 25 to 30 and I am sure by May 28 results will be announced and so you can fill your form for the same .
All the very best!!

Hey Shuvam!
For admission in St. Xavier's College, Kolkata with B.sc Honours in microbiology, you must have Mathematics as a compulsory subject.
Kindly go through the link of eligibility criteria
http://www.sxccal.edu/admissions/SXCAdmission2018/UG8102/EligibilityCriteria.htm
I hope this helps.
AIMS PUNE admission procedure:
https://www.google.co.in/url?sa=t&source=web&rct=j&url=http://www.aimsinstitute.in/admission_details.html&ved=2ahUKEwjzkI3z44rbAhXZXSsKHV0zBR8QFjABegQIBxAB&usg=AOvVaw1eZhdLNBZb9OtnWVd8CcgI
AFMC admission procedure :
http://www.afmc.nic.in/#nogo22
Good luck Shuvam!

If you have any grievances, you can complaint to the concerned mail id given in the CBSE website.

Yes, you can get into PEC. CBSE Percent is also good. Go for it. You can get admission over there.