While you do have the ability to delete a workspace in Notion, a teamspace works a bit differently. As of this writing, you can’t delete a teamspace, but you can archive it. This removes the teamspace and all of its pages from your sidebar. You must be the teamspace owner to archive...
5. Type the teamspace name and choose the “Archive teamspace” option. Typing your teamspace allows Notion to verify your identity as a team owner. If you want to delete the teamspace, select the red “Archive teamspace” option. Otherwise, select “Cancel.” 6. Choose between “Move pages...