[Koala818]

I don't really understand where that piece of code comes from but here's the easiest way to do this:

pawn Код:

public OnPlayerEnterVehicle(playerid, vehicleid, ispassenger) //When a player enters a vehicle
{
    if(InfoJucator[playerid][zMasinaLic] < 1 && TakingLesson[playerid] != 1) //If the player does not have a license and does not take any lesson.
    {
        if(!IsABmx(vehicleid))// If the vehicle the player is entering is not a BMX, then don't let him drive.
        {
            SCM(playerid, COLOR_WHITE, "Nu ai licenta de condus.");
            RemovePlayerFromVehicle(playerid);
        }
    }
return 1;
}

Read what's commented (The green part after "//") for a better understanding. I hope this help, if not, be more explicit of what you're tryin' to do so we can help.