You guys are hopeless. Are these really men I'm stuck here with? Fine, let me take the helm.
What a human needs to survive is food, water, and shelter. Including a fire.
Fishing line. Take some plant fibre, weave it into a crude rope, tie the end. For a hook, find a shell on the beach or something and work it into something hook shaped. Bait the hook with fruit or something. Worst case scenario, sharpen a stick. All who can swim, take up a harpoon.
For those who can't swim, make a fire. Bow drill. You rick and morty fans should have a high enough iq to whip one up. After that, split into 3 teams. Water scouters, Fire Watchers, and wood gatherers.
"But bahamanon, how will we gather the wood?"
Take a rock. Take another rock. Smash them together until you have something jagged enough to dent a tree.
Half of the wood will be set aside and buried under the sand, covered with oily leaves. That's our firewood. With the rest, we build our shelters.