on rightclick on sign:
    line 2 of clicked block is "checkpoint"
    line 3 of clicked block is "[rightclick]"
    set {checkpoint.%player%} to location of player
        message "&6 2つ目のチェックポイントを設定しました!"
    if player has permission "skript.admin":
        message "&7Location of player"
on rightclick with nether star:
 cancel event
 if clicked block is sign:
     stop
 if {checkpoint.%player%} is set:
     teleport player to {checkpoint.%player%}
     stop
 else:
     message "&c 2つ目のチェックポイントが設定されていません!"