Advice for removing thousands of pages that were indexed by Google search

Hi everyone, I looked through this forum but couldn't really find any answers for my dilemna. I completely revamped my website and removed about 6 thousand items that were listed, many of them indexed on the google search engine. I'm trying to figure out how to get them all removed! I looked at my google console but their only solution is to remove the pages one by one, which is not really do-able. My skill level is novice so before doing something like modifying my robots file (currently it just has the "user-agent *" and the disallow cgi-bin commands) I thought I'd throw it out there and see if anyone could give some advice. Thx

You could start by uploading the Sitemap mod at https://www.zen-cart.com/downloads.php?do=file&id=367

Publishing it to the SEs should take care of your problem quickly.

Ok thank you for the recommendation.

You need is to make certain the links are returning a proper 404 and they will be dropped eventually