Open Outlook and go to the folder containing the emails
Click the search box and enter a sender, subject, keyword, or date range
Select one email, then press Ctrl+A to select all matching emails in the folder or search results
Hold Shift and click to select a range of emails
Hold Ctrl and click to select specific emails one by one
Press Delete to move the selected emails to Deleted Items
Press Shift+Delete to permanently delete the selected emails
Empty the Deleted Items folder if needed
Use the Cleanup, Sweep, or Archive options if available to remove many related emails at once
Sort emails by sender, subject, or date to make bulk selection easier
Use filters to narrow down emails before deleting them
Repeat the process in other folders if needed