_dir = getDir vehicle player;
_pos = getPos vehicle player;
_pos = [(_pos select 0)-5*sin(_dir),(_pos select 1)-5*cos(_dir),0];
_veh = createVehicle ["MQ9PredatorB",[_pos select 0,_pos select 1,1], [], 0, 'NONE'];
_veh = setVariable ["MQ9PredatorB", 123456, true];
Player moveInDriver _veh;
_veh setDir _dir;
You were partially write at some points, but this is a working vehicle spawn script atm.
Change the classname ("MQ9PredatorB") to spawn your requested vehicle.