That all depends on WHICH solitaire game you're playing.
If you're playing the Microsoft Solitaire Collection, then you can't reset it. If you uninstall it and reinstall it, it will simply restore the user data that was there before.
The only way to reset it is to change your Microsoft account, which will mess up a lot of things. Yeah, I've always liked resetting my scores from time to time, but can't do it here, I'm afraid.