How do I give player points when a person joins a game?

I know it may have something weird to do with http or something.

Possibly like

function OnPlayerJoined(game)

local pointsToAward = 1

game.Players.PlayerAdded:connect(function(player)
	game:GetService("MarketplaceService"):AwardPoints(player.userId, pointsToAward)
end

Try the wiki.