A dark-skinned man in white shirts and a black sleeveless shirt flips his skateboard on a cement surface surrounded by tall buildings and palm trees.
a man flips his skateboard on a cement surface
dark-skinned man flips his skateboard   is the same as man flips his skateboard
A man (dark-skinned) flips his skateboard on a cement surface as part of man's description surrounded by tall buildings and palm trees.
The person is a man because he is a dark-skinned man.