How do you get out a splender that is between your fingernail, that has been there for two weeks now?

Do you mean splinter? I would suggest a very thin pair of tweezers. That's what I do when I get splinters. You just have to be careful you don't push the splinter farther into the skin.

Make sure area is very clean and dry.Place heavy duty sticky tape securely on area.Slowly , peel tape back... Repeat if, necessary.Sometimes , this works.

And you may have to trim the nail way back to get to it, and if nothing else works, a trip to the doctor may be needed