Selecting a player?

In a game I'm creating I need to know the basics to selecting a player to attack. Like survival 303, when you click on a player, with your sword it damages them. What part in there, and make it so an animation will play, showing the player swinging their sword, yet the player has damaged the target?

wait(2) --Bugs if you don't wait

local players = game.Players:GetPlayers()
local randomplayer = players[math.random(1, #players)]
print(randomplayer.Name)