Cody keeps biting his paw

heya guys just a little adivce needed cody has been biting his back paw so much that its literally red raw and has puncher marks what could be causing him to do it xx

Not sure but maybe something is stuck in his paw? Maybe allergies.
How long has he been having this problem?

As mentioned above; could be a bite, sting or an allergic reaction to something. Some dogs will lick/chew an area if it's painful, also. Are the puncture marks from his own teeth? Either way, I would pop him into the vets for a check - his foot could get infected easily.

If you cant see anything embedded in his paw pop him to the vet

i would bath it in warm water, dry as far as you can & rub some antiseptic or coco nut oil into it. if it doesn't help over the next 24 hours then a trip to the vet?

With paws you have to be careful what you put on as the dog can lick bite etc i would just wash the wound in warm salt water and dry thoroughly till you can get a vets appointment