Inquiry on treatment of multiple dark spots on back without sun exposure

I am concerned about the numerous black spots that have appeared on my back.

Can these areas be treated?

Although this area is rarely exposed to sunlight, spots have appeared. Most of them are not protruding and have the same height as the skin, but have changed color.
I have several spots on my back, so I don't know if this is a natural phenomenon that occurs with age.
 
I would like to inquire about a treatment method that can effectively remove this mole.
I would like to ask for advice on specific aftercare methods and expected recovery time to prevent pigmentation and ensure clean healing of the wound after back treatment.