How do I make other players catch on fire, by using one player who is burning?

Hey guys, I just recently got into scripting. Now I am stuck with an idea I can´t finish, which is creating a fire on a player by letting them step on a part and then give it to someone else, to make them burn and die from it. They also have the chance to give it back, since the fire is timed.

Altough I have absolutly no idea how I am supposed to find the players that can be given fire to.

It´s supposed to work in the mechanic of a game called "hot potato".

fire = true
fireinuse = false
Firetime = 5

function Iamit(part)
    if not fireinuse then    -- Avoid multiple fires to start
        fireinuse = true

    fire = Instance.new("Fire")  -- Create the fire
    fire.Parent = part

    while
    (part:findFirstChild("Fire") ~= nil) do  -- find where the Fire is and take the dmg
    print(part)
    Firetime = Firetime - 1
    wait(1)
    print(Firetime)
    if Firetime <= 0 then part.Parent.Humanoid.Health = part.Parent.Humanoid.Health - 100 -- kill
        Firetime = 5
        break
        end
end
    fireinuse = false
    end
    end

firePart = game.Workspace.takepart
firePart.Touched:connect(Iamit)

function Youareit(part)
    fire = part:FindFirstChild("Fire")
    fire:Destroy()

if not fireinuse then    -- Avoid multiple fires to start
        fireinuse = true

    fire = Instance.new("Fire")
    fire.Parent = part

    while
    (part:findFirstChild("Fire") ~= nil) do  -- find where the Fire is and take the dmg
    print(part)
    Firetime = Firetime - 1
    wait(1)
    print(Firetime)
    if Firetime <= 0 then part.Parent.Humanoid.Health = part.Parent.Humanoid.Health - 100 -- kill
        Firetime = 5
        break
        end
end
    fireinuse = false
end
end

local player = game.Players:GetChildren()
local character = player.Character.Humanoid
if not character or not character.Parent then
 character = player.CharacterAdded:wait()
end


character.Touched:connect(Youareit)