I have a lump on my third finger n on my toe on the joints n it hurts. what can it be?

Could be a corn: Or a bursitis or a mucoid cyst amongst many other things. If you saw a podiatrist in person, they can tell you in 2 seconds what it is. If they are unsure, a biopsy is likely needed.

Could be arthritis: In general, arthritis is swelling in the joint and because you describe 2 sites where there is pain and the finger with a lump, it is possible that this may be a sign of arthritis. Get examined and the doctor will do a work-up which will include bloodwork and radiographs. If this is a condition like arthritis, you want to have it diagnosed early on.