Deleting and Reconstructing new website

If you want to start a new site in the same place from a completely blank slate, delete all of the files under:

/wp-content/plugins/
/wp-content/themes/
/wp-content/uploads/

And, delete the old site’s MySQL database (check your hosting provider’s documentation for specifics).

Then, to start the new site, start at step 2: https://codex.www.ads-software.com/Installing_WordPress#Step_2:_Create_the_Database_and_a_User