It sounds like a form of eczema. I get something similar on my hands. I try to avoid putting them in water, use rubber gloves for washing dishes etc., and loads of hand cream. It usually clears up in a couple of weeks.
That being said I had a really weird rash on my hands and forearms last Spring. The spots were fluid filled, like chicken pox, and were purple/red in colour. They were really itchy and prickly to begin with, but after the itchiness calmed down the spots remained for months, the last of them on my hand just disappeared at the end of December. I'm of the belief that it was a covid skin rash, I had no other symptoms.