I used to sell feet pics and had built up some nasty callouses after years of athletics.
A. Gentle scrub. I didn’t ‘scrape’ the callouses away but just kinda wore them down. I used this (1) for a scrub. It’s not too rough and wont tear through skin.
B. Intense moisturizer. I would get thick socks and put them on after lathering my feet in lotion every morning, night, and after shower. Or just when I felt like it.
C. Wear heavily padded slippers. Prevent callouses by keeping your feet up when you can and staying off of them. When you’re around your house you can wear thick slippers to cushion your feet.
This is what worked for me and I hope it helps you too!!