I will present several endgame positions as problems to illustrate endgame principles and cases. In figuring them out perhaps you will learn a little also.
1) Mating with a rook and king against a lone king involves limiting the other king's moves. See if you can mate in 3 moves
2) Rook pawns (pawns on the a and h files) give the weaker side chances to draw not available with center pawns. Black to move and draw.
3) Sometimes less is more. White to move and win.
4) White to move and draw. It does not have an exact solution, but if you notiice Black cannot both queen his pawn and stop White's pawn from queening. He can do only one or the other. This is an old endgame study by Richard Reti.