So a lot of players have problem finding a nice and clean area to start building their first base.....
Well lets have a look on the map of the game.So as soon as you start moving around take your time gather the items from the plane but dont stay to long near the plane because the cannibals will start the patrol around it.Then the best place to go is the beach.
Watch the red arrow on the picture of the map!.
As soon as you go to the beach you will see a big tree
Thats one of the best places to make the base because it requires a single line of deffensive walls to protect you and your buildings!
Just make some traps outside the walls and you will be good
You can have a look on my base there if you want some ideas

So you guys might wondering why near the beach and not somewhere else on the rest of the map
Well because:
1)No cannibals beyond the walls
2)The boat is near too
3)Birds and turtles are everywhere so you will have plenty amount of food
4)Plenty amount of loot around the beach and old pots in the tent near the anchor

I hope this helped you guys but if you are still confused you can watch a related video(not mine)

https://www.youtube.com/watch?v=42ygRMrJ-c0