// if we press a button, move the obj_player
if (keyboard_check(vk_left)){
    // move the player vk_left
    x = x-2;
}
if (keyboard_check(vk_right)){
    x = x+2;
}
if (keyboard_check(vk_up)){
    y = y-2;
}
if (keyboard_check(vk_down)){
    y = y+2;
}