The wound looks a bit deep, and the swelling with color change indicates there is inflammation happening in that area. The cause of the wound should be identified , and then only specific treatment can be planned for him. Kindly check if there are maggots inside the wounds. If so, then he may need them to be removed first before wound dressing. Then, he may need systemic medicine for clearing the infection, inflammation, and swelling.
Next Steps
Try to show him to a veterinary doctor either offline or online for further diagnosis and treatment.