Hi Sourav,
There are several online websites from where you can enroll yourself for an interior designing course but be aware as some websites don't give certificates on completion of the course so make sure that you apply for a paid interior designing course where they clearly mention that they will give you a certification of accreditation upon completion of the course.
There are also some universities and institutes in India where you can enroll yourself for pursuing Bachelor in Interior Designing through distance education. Some of these colleges are:
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