Quarter sized hard lump under skin right shoulder blade area with a small bruise above it has been there for sure 2 1/2 years what is?

Many possibilities. If there is no pain, no increase in size, unlikely to be cancerous. If increasing in size, or painful, you need to see a general or ortho surgeon for eval and likely work up or excisional biopsy. Small non painful lumps are frequently inclusion cysts, fatty tumors, possibly a cyst coming from a local joint. For reassurance, have your pcp take a look first.