Hi Shubham. There are various courses available after BCA. It depends on your interest which makes a course best or worst. Hence, a short-list of courses after BCA is given as follows, you can opt one of them as per your aspiration:

Master of Computer Applications(MCA)

Masters Degree in Information Management (MIM)

Masters in Computer Management (MCM)

Post Graduate Program in Corporate Studies (PGPCS)

Information Security Management (ISM)

Master of Business Administration (MBA)