My husband has a grey dot on his foot it does not hurt or itch or peel he started to grow another one it coming from the inside of his foot.

Wart?: You may consider it being a plantar wart which often look gray and can increase in size without pain or itching. If he's growing another one, he may be reinfecting himself as it is caused by a virus. You can try over the counter wart removal products like salicylic acid or bichloracetic acid or self-freezing kits. Or you can have your doctor look at it and possibly freeze it with liquid nitrogen