Hey Aspirant,
Yes, you can do Bachelor in Pharmacy (4 year graduate degree) course just after 12th as the course requires minimum eligibility as :

• A candidate must have passed 12th examinations with Physics and Chemistry as compulsory subjects and one of these Biology or Mathematics subjects
• The candidate must have scored minimum 50% marks (45%marks for reserved category) in the qualifying

And yes, one can do M.Pharm ( 2 year Post-graduate degree) after B. Pharma., as masters course in Pharmacy requires that you must have obtained a Bachelor's degree in Pharmacy for pursuing it and you must have scored minimum 50% marks in the qualifying degree.
Good Luck!

Dear aspirant,

Yes you can definitely pursue M. Pharmacy after B. Pharmacy, until and unless all your exams are cleared in bachelor's degree.  You can also do B. Pharma  after your +2, if you fulfill eligibility criteria.
Best of luck for future!!