Celtic knows sit, down , stand, come, wait, stay, break(release word), leave it, take it, lets go(informal loose leash walking), kennel, hup up(jump in car, couch etc), quiet( sort of), back(move away from door etc) I consider these must know to be a good companion.
He is learning- stack, foot(move your foot), fetch, heel, spin left and right play dead, paw, finishes around and swing, find it , all the agility equipment names , touch , bottom so far. There are others to be learned with obedience, conformation and agility that we have not started. These are fun for dog sports.