Found lump (walnut size) in groin. Hard and seems fixed to top layer of skin. No pain, can squeeze from all sides but can really move it. Everything I read says cancer but are there other possibilities? No other symptoms besides getting a cold two wee

Hard groin mass. The lump you have described is highly suggestive of cancer. See your doctor and he will recommend biopsy or excision of the lump for a definitive diagnosis.
Get seen now. Gordon, this may be nothing but an uncommonly large dermatofibroma that you hadn't noticed up to now, or a nasty case of nodular fasciitis, or any of several other entities, but you need to be seen without delay by your physician.