[Abagail]

You can't. I replied to your other thread - https://sampforum.blast.hk/showthread.php?tid=550612 which is basically the same thing.
Basically aiming can be roughly simulated using animations.

pawn Код:

public OnPlayerKeyStateChange(playerid, newkeys, oldkeys)
{
        if(newkeys & KEY_WALK)
        {
              ApplyAnimation(playerid, "ped", "ARRESTgun", 4.0, 0, 1, 1, 1, 1, 1);
              return 1;
        }
        return true;
}

Just an example of how such a thing can be accomplished.