My scar on the sole is like callus. I had it from cauterization of plantar wart. How can I removed it? It is painful (photo)

I am very sorry you are having this difficulty. When I was in training more than three decades ago, one of my professors at the time, a renowned specialist in viral infections of the skin, explained to us that his interest in the field stemmed from the fact that at age five a general practitioner burned off with cautery a plantar wart on the sole of his foot, which resulted in a scar that left him with a lifelong limp. I remember how strongly he cautioned us not to resort to using aggressive, destructive methods, such as cautery (and these days that would also include carbon dioxide lasers, etc) to remove plantar warts unless all else had been properly tried and for sufficiently adequate periods of time. From the photo, the scar (if in fact it is only a scar and not a recurrence of the wart) appears elevated, so a trial of intralesional anti-inflammatory agents, such as triamcinolone and 5-FU may be in order. Additionally, or alternatively, the use of an injectable volumizing filler placed beneath the scar may help to cushion the ball of the foot and ease the pain. However, if, after paring down the surface, it appears that there is actually residual or recurrent wart tissue, then additional paring, plus topical TCA, supplemented by the daily use of at-home anti-wart preparations would be appropriate. You would be wise to consult with a board certified dermatologist. Best of luck.

Thank you for your photos. You could benefit from laser skin resurfacing which stimulates your body to fill in under the scars with collagen.  You could also try injectable fillers to raise the scars and give your skin a smooth appearance. Hypertrophic scars can be treated with steroid injections that will diminish their appearance. For more information, I recommend getting a in person consultation with board-certified dermatologist.