Delete Website Files Using Cpanel, Keep Email

Several years ago, my WordPress website was hacked and I deleted it but I kept using my domain based email account. I would like to make sure that all the website files were deleted properly, without affecting my domain-based email account. Could you give me instructions on how to do this so I have the option of reinstalling WordPress.

Currently the old files are taking up around 4 gb of space on my hosting account.