There are many types of surgeries in elbow. What surgery was done in your case.. was it some bony procedure or some soft tissue problem.. For fracture, it may take around 6 weeks for healing. Soft tissue may take around 3 weeks to heal. I think your surgeon will guide you in a better way regarding time if healing in your case.
Next Steps
You should take more of protein containing foods to build up the muscle strength. you can also take milk green vegetables, fruits ( if you are non diabetic)..