You can't install/uninstall Windows Media Player. But you can hide and unhide it in Control Panel>Programs and Features (it's under Media).
You can't reinstall sound. But you can reinstall the sound drivers if something is wrong with them. just download the right files from the maker site and go ahead.
But it might be that something is fundamentally wrong with your system and you have to refresh or reset Windows.
This one tip will help you sleep better tonight
A few seconds are all you need to get a better night's rest.