Your objective is to clear each stage for Robin Hood's arrival. To do so, you need to make sure there are no guards present (for example, by dropping an apple on their head) and that all food and treasures are on the ground so Robin Hood can collect them. To do so, simply click on food to drop it down. You can also click on anything made of wood to make it disappear. Make smart choices and beat the guards and the levels by selecting in the right order!
Once all treasures and food are on the ground and all guards are gone, click (with mouse or finger) anywhere on the stage and Robin Hood Will appear. Then click on the food and treasures for him to collect.