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If the handle is seized on the stem then you will probably need a handle puller to get it off.
If you can get the handle off the chrome trim behind the handle will need to be removed so you can get to the hex that holds the stem (what the handle is attached to) out
Once the stem is out you may find that the washer at the end of the stem is gone. You will probably need to replace the washer in any event. But you still aren't out of the woods since you need to be sure the seat inside the valve (faucet) body is not pitted or grooved. I suspect it will be. If it is you are probably out of luck since the chances of finding a seat are very slim
You are probably better off just replacing the the entire valve( faucet).