u/Intelligent_Buddy_67

I tried the helicopter crash start a few times, most of them was a small island with few animals, trees etc. What do I do? Once I tried swimming, but had to leave behind every single item, and luckily made it to the shore alive and survived a few days after that. Is there any way to train swimming so I can leave with some items? Is there any way to make a boat? I don't understand the vehicle system, but tried once and needed tons of leveling and manuals and tools and items that are impossible to get on the island. Help!