I checked your domain, and it is registered since 2011, 12 years ago, that means this domain has been used for a long time and there is a lot of data: https://prnt.sc/11SCSA9Eat0u
I also looked at the 404 error links you sent, it seems like the link was automatically generated from a malicious code, not the link from the pages or posts that have been deleted.
Your website also installs a lot of plugins and has not been updated, so it is possible that the website has been infected with a virus and attacked, leading to inserting strange links into the website.
This error has nothing to do with our theme, so please fix it yourself or find someone with experience dealing with this problem to help you.