How do I use coroutine?

This is not a request site but here is loop explode script: Change Player1 to your name

function Explode()
    while true do
        wait(1.5)--Recommended not to change
        ex = Instance.new("Explosion", game.Workspace.Player1.Head)
        ex.Position = game.Workspace.Player1.Head.Position
    end
end
wait(3)
coroutine.resume(coroutine.create(Explode))
wait(3)

Hope I helped!