Is there is entrance exam for taking admission in Diploma?

Usually, there is no entrance exam for any Diploma course but if you are looking for any specific college then you have to directly contact them.

Dear Mansion, There is no entrance exam conducted usually for any Diploma course. You can analyse your course and start working to get a Diploma in that specific specialisation. If you have any course in mind please let me know so I can help you with the colleges to pursue your higher studies.