Near sensors are used to detect objects that comes near them.
Our player character will go near a monke and it goes up.
Add Suzanee, add a near sensor and type player in the property field. Select our default cube and make them movable with motion sensors how you'll be able to move it. Add a player property to it. Now select our monkey and add a motion actuator and make it go up. If you want the monkey to go up and down, set our monkey's phyiscs type to Dynamic. Connect them if you haven't and run the game.
If your monkey is not detecting the player, you need to enable Actor in the physics type. Now try running the game and it must work.