Complex sentence: Tony eventually decides to declare war and take over the North Side and sends one of his best men and close friend, the coin flipping Guino Rinaldo (George Raft) to kill O'Hara in a florist's shop that he uses as his base.
Split into simpler sentences: Tony eventually decides to declare war and take over the North Side. He sends the coin flipping Guino Rinaldo (George Raft), one of his best men and also his close friend, to kill O'Hara in a florist's shop that he uses as his base.