been playing for a couple of years, having trouble finishing my game,do no know what to do at the end, to win the gamw, can anyone help me?

Have you tried going through the various tutorials? Josh Waitzkin's Academy has an endgame course which would probably help you.

You have to check mate your opponents king. Many beginners like to "clean the board" and they end up stale-mating opponents king.

Check-mate ends the game.