guys pls help my analytics showed a strange drop and when I checked, the bare domain throws a certificate warning. the www version is fine.

This site can't be reached
Check if there is a typo in my-shop-site.example.
If spelling is correct, try running Windows Network Diagnostics.
DNS_PROBE_FINISHED_NXDOMAIN
I'm using the default DNS editor and pointing teh site at a git-based pages host. I think there's still an old A record from the previous host but I'm scared to delete things I don't understand. could someone explain how apex and www are supposed to be set up? A short explanation of what each record is supposed to do would help alot. any ideas??