Will it be fruitful to pursue MBA at the age of 30?

Yes, it can be better if you are doing it from any premiere institute like IIMS, TISS, XLRI, etc. One should try for PGPM from top institute with experience of more than 4-5 years. Best of luck.

If you are already employed somewhere, it adds value to your learning. You may know few tools and particularly, if you are doing a full time or a part time executive MBA from institutes like JBIMS, IITs, FMS – Delhi, NMIMS, Symbiosis or KJ Somaiya, it gives you lot of insight such as presentation sk

It depends on your interest. If you get a good job with a good income, then please don't. Otherwise, you should go for it as it will help you get to get better job opportunities and broaden your horizons.