Dermatologist. What you should do is to go to see a dermatologist as soon as possible. Your dematologist will be able to tell you the diagnosis and deliver the necessary treatment- a resection - to remove it.
Have it removed. It may not be possible to know what kind of cancer a lesion may be. Have it removed and the tissue examined by a pathologist. If it is basal cell cancer, that will be enough, if, god forbid, it is melanoma, additional tests and treatment may be needed. Do not delay consulting your doctor.
Different animals! Basal cell cancers are l slow growing locally invasive takes years and years before eroding into a major organ, appear as shinny blister, ulcerates slowly nibbles like a rat ( called rodent ulcer) contrary melanoma is lethal, moles change in color etc seen visible parts of body , skin nail beds rarely GI gu tracts. Immediate attention is required, earlier stages wide excision will cure.