Your ship capsized in a terrible storm but you managed to swim ashore. Exhausted, bruised, and alone, you stand up on the beach, feeling the cold wind against your drenched clothes. How long can you survive?
Building a shelter and acquiring water are your top priorities. To avoid parasites, boiling the water is the sensible thing to do. However, getting a fire started without lighter or matches will be a challenge.
Hunger will be your next problem. Forage for plants and fruits, craft bow and arrows to hunt the local wildlife or focus on trapping or fishing. Bears, wolves and other predators may roam the island so be careful that you do not end up on their menu!
Make sure your diet is varied or you will eventually suffer from nutrient deficiencies.
Loneliness will be your worst enemy long-term. Challenging yourself mentally will be important to not descend too quickly into insanity.