I check the Search Consol regularly and in the last week I've seen reported hundreds (274 today) of these "errors" being registered. (See image Capture 2)
They seem to being generated from non-existent pages (See image Capture 3)
Why are these being generated and how to stop them? Also - do I really need to create a redirect for all these false pages?
Google Search Console errors are a good thing to check on as part of an ongoing SEO task for a healthy store. You can see HOW Google discovered the broken link usually by clicking on the individual link then seeing where it was discovered. Sometimes it is a link from your own store, in which case you can update. Sometimes Google discovers these 404 pages from a link on another website, which can be spam or a legitimate past backlink. In your case, it could be from a previous owner of the domain or even a platform migration that use to have search results at different address and redirects were never done.
If it is a legitimate page for a page that should not exist and there's no similar variants, then most times you can let it 404. That is a legit 404. If it was an old page though, if there was a migration, or you just want to capture backlink value to those pages that 404, then I'd recommend doing a redirect.
The links are being generated from false pages. This is a link that has been reported as "faulty" returning a 404. This page has NEVER been created.
These are the pages it is supposedly residing. Both these links also return a 404 response. They also have NEVER been created. I don't know if it is significant that seem to be affected by "catalogue search" yet when I test the search function it is working fine. There are 648, 404 errors TODAY - all in the similar format.
Is the Shopify website generating them?