Oh those are pretty big games haha, the recent dark and darker release has people playing it all over twitch.
Basically, you spawn into a map with nothing. It’s both pvp and pve, and the usable map gets smaller over time (fortnite/battle royale style). You pick up loot throughout the game, lose everything when you die, and there are only x points where you can “extract.” If you extract, you can store that loot in your vault and choose what items to bring into the next match, so you have an advantage over other players.