I hit my head on the edge of wall when i was younger twice causing a pencil like dent in my forehead no medical treatment. now years later can i get medical treatment/ surgery? can brain damage be reversed? can anything be done for old tbi? please!!?

The dent happened because your skull was probably soft at young age and there is no need to fix anything at this time. If there was true lesion below the skull at the time of the accident, e.g. epidural or subdural hematoma, it is too late and there is no benefit of doing something for that.

You describe a closed head injury that left signs of the impact on your forehead. Not clear if you had either brain damage or "TBI", and depending on your current symptoms, re-evaluation with updated therapy may not be productive. If the deformity bothers you, a visit to a plastic surgeon may be useful.