There is no such thing as an unvirgin hymen the hymen is broken during intercourse.

Males do not have a hymen. Theoretically, you can say that the male's foreskin is their hymen equivalent, as it serves the same purpose for the penis as a hymen does for the vagina.

There are no exercises to break the hymen. The hymen cannot be broken but can be torn if penetration is rough or forced, simply exercising is not going to tear the hymen.

Yes, you can see and feel your hymen. The hymen is tissue that surrounds the opening to your vagina, thus you can look at your vulva in a mirror to see your hymen and you can feel your hymen just by feeling around the opening to the vagina.

The hymen cannot break, it can be torn as a result of rough or forced penetration. You can identify a torn hymen by looking at the hymen, if you know your body well you will be able to see the tear.