When the plantar loses fat and sponginess, what can you do? i feel like i am treading on hot coals all the time?

First steps: First step would be to use cushion insoles to help soften each step. Losing weight and hydrating could help with the overload pain. If those don't seem to relieve the pain, you may need specialty treatment. Best of luck.

Wear cushioned: Insoles but if you have weird sensations you may have neuropathy as well.

Foot orthoses: In most cases of plantar fat pad atrophy, accommodative foot orthoses can cushion the feet and offload problem areas to provide pain relief. Talk to a podiatrist to see if this is an option for you.