Q: hello i would like to know how can a man get rid of unwanted muscle mass

A: That's very easy to do -- simply lose weight with minimal or no exercise by undereating. I do want to caution you however that in virtually all cases where either men or women blame extra muscle for undesirable appearence or unwanted bulk, the actual culprit is FAT and not muscle. The only bodypart that relatively often gets excessively muscular for an average person is their calves -- especially for runners. But unless you have been training for years in strength and power sports or weight lifting, it's very unlikely that you have excessive muscle in places other than calves and VERY likely that instead you have extra fat.

If it's really extra muscle that's causing the problem, then you should have good definition overall, have a hard body, be unable to pinch more than a fingerwidth of skin on your legs or abdomen or chest, be able to see blood vessels and individual muscle strands under your skin in the shoulder area, etc. If it's extra fat, then you should have a soft body and be able to pinch a good chunk of skin on your abdomen or other body parts.

I literally never seen a case when somebody who thought that their extra bulk was caused by muscle was correct, besides the calves situation I described above. In all other cases the person was convinced they had too much muscle when in reality it was too much fat. So be very very very sure that you really want to lose muscle because losing it is unlikely to improve your appearence AND will also make you much more vulnerable to new fat gains. If you're certain that that's what you want however, all you need to do is stop all exercising and eat quite little to lose weight.