how do i make a script that detects when the player dies and prints out value?

You can do this with the Humanoid.Died event.

Read more here

i.e

game:GetService('Players').PlayerAdded:connect(function(player)
    player.CharacterAdded:connect(function(character)
        character:WaitForChild("Humanoid").Died:connect(function()
            print(player.Name .. " has died!")
        end)
    end)
end)

Hey RealRexTeam,

The humanoid has a .Died event that you can use to detect when the player dies. I recommend just attaching it to the .CharacterAdded() function so that it runs at all times while the player is alive and it is well formatted that way. Here, I'll show you an example of it below.

Script

local plrs = game:GetService("Players"); -- The players service

plrs.PlayerAdded:Connect(function(plr) -- PlayerAdded anonymous function with parameter of the player.
    plr.CharacterAdded:Connect(function(char) -- CharacterAdded anonymous function with parameter of the player.
        local hum = char:WaitForChild("Humanoid"); -- The humanoid in the Character.
        hum.Died:Connect(function() -- .Died anonymous function
            print("Humanoid has died.") -- Prints "Humanoid has died." 
        end) -- end for .Died function.
    end) -- end for .CharacterAdded function.
end) -- end for .PlayerAdded function

Well, I hope I helped and have a nice day.

~~ KingLoneCat