[Bax]

Hello. I don't get it how to use commands using samp gui.
i.e. When I type /kick it shows me a dialog which asks me for players ID, and so when I input the ID shall i use a variable to store players ID or is there another way?

[Calgon]

If you mean the SA-MP dialog system, every response triggers the OnDialogResponse callback. All you need to do is track the response and kick the player.

See here for more information.