Former EMT here: the rule of thumb with impaled objects is “stabilize for immediate transport” so you are on the right track, but you probably would want to leave enough of the arrow shaft not cut off to be able to immobilize it— so it doesn’t move and increase tissue damage. Then surround it with gauze pads and pressure bandages. Just bear in mind he’s got to be gotten on a gurney and into a truck, so think about how that’s going to be accomplished when you bandage the wound. Stop bleeding first, stabilize second, prepare for transport third. If you can’t stop the bleeding with the arrow impaled you will need to apply a tourniquet above the wound.