The Walls to the maze will be made of objects.
You will need to have designed a sprite for the wall. Then create a wall object and set is a solid.
Lay out the walls round the edge of the room by either dragging the wall objects on one at a time, or by selecting the wall object, holding the Alt-key and painting the objects into the room with the mouse.
When moving the player using the co-ordinate system, we can use the Collision event to detect if we have hit a wall.
When moving the player using the speed and direction variables, we need to check each step if the player has hit a wall, and if so, have it bounce back.