I agree there’s not much you can do at home with bunny teeth, and I can very well understand about your finacial situation with your dad being sick. What you have to see to while you save up money for a vet-visit is that your bun eats like he should. The incisors is for pulling food into the mouth, the actual chewing is done with the molars. Most bunnies can learn very well to live without incisors (some have to have them removed completely), but it’s important to check so he really keeps eating like he should. Otherwise his tummy will suffer, and that’s always serious.
If you notice he has trouble eating you could try and support-feed him with critical care + baby fruit purée etc on a plate, (pellet-mash will do if you don’t have CC), because then you’ll know he gets all the nutrients he needs. Which of course is extra important for an injured rabbit.
My best recovery-wishes to your father.