I had ankle surgy about two years ago leaveing with seven screws a plate I brused it bad now there is a knot been there for 3 months what should I do?

Screw head. The knot is probaly a screw head it can be removed if loose amd backing out or interfering with shoe wer otherwise leave it.Follow up with surgeon.
Ankle hardware. You will need an x-ray to determine if the hardware is ok.
Bursa. May also be a bursa (like a cyst) over the plate or screw. See your surgeon.