Yes. I understand that! But in Lightsail, the way to set up an A record is to fill this screen attached.
. As you can see, I MUST enter a subdomain. I'd like to leave the subdomain blank, but I get the error that you can see. Should I perhaps go to the DNS server on modify it to point to x.x.x.x/sub_crud? Or is there an easy way to enter an A record without a subdomain?