Dear student, with an AIR of 245 in the GEN category for NIPER M.Tech, it's highly likely that you can secure a seat. However, the specific NIPER and specialisation depend on the cutoff trends and your chosen field. Usually, ranks up to 150-200 are considered good for top NIPERs like Mohali, Hyderabad, and Ahmedabad, but your rank is close enough that you have a good chance in these institutions, especially if you are flexible with your specialisation.
Dear student, you can check out a list of top colleges for Diploma in Pharmacy here - https://www.collegedekho.com/diploma-in-pharmacy-pharmacy-colleges-in-india-listing-23487-1870-19163/
Dear student, you can attempt NIPER mock tests on various test-prep sites online. The official mock test has not been released yet.