I will drop this year and prepare for medical. Will it be difficult to get admission next year in DU and PU? Please make it clear

There are many students which take a drop and give time and dedication to their studies. So its common.
There shall be no such issues if you plan to take a gap for a year.
But make sure if you take this gap then you are able to show its worth so that you don't have to explain it much that why you took the gap.

Hope this helps.