How do I restrain a player's movement ?

How can I "delete" the left key for a player in a layout, like if I only want him to go to the right, up and down, but he can't go back (left) ?

Thank you

If you set your character object's behavior to include platformer, you can then set the 'default controls' to 'no' and in the event sheet for each key you want to character to move use 'stimulate object movement' and select the action you want the character to perform.

are0planes has hit the nail on the head here. Just make sure you add the Keyboard Object too, so you can do this

Perfect guys, thanks ! <3