You can move around using the arrow keys, and in order to use abilities, you have to click on them (on the right side of the screen) and then where you want to use it on the map (if you want to shoot a fireball for example, you have to select "fireball" then click on the tile you want to shoot it at). Pick up items using G when standing on them and then you can use them by clicking their icon on the lower part of the screen.