I couldn't find instructions for this on one nice page, so I'm making this one. This might not be the only way to do it but it is a way that worked. I'm listing the pages that worked for me as a thanks to them.
First I had set up the A record in the DNS as namesilo suggested. But I then changed to the actual Google IP numbers as found on this page:
https://seoneurons.com/blogger/setup-custom-domain-name/
This may be overkill. But it was part of my complete process so I include it here. Remember, the CNAME records come from Blogger when you set up the custom domain there. When obtained, enter them in to DNS Updater.
Second, I generated CAA records using this site, clicking Google and Let's Encrypt as the Authorized Certificate Authorities (step 3 on page)
This site was a huge find for me!
and entered them as CAA's in the DNS Updater on the Domain Manager as illustrated here (for Google Domains but basically the same for namesilo as well).
Notes:
The Https Availability in Blogger Settings does not work until the CAA for Let's Encrypt is added to the DNS Updater in the Domain Manager (the Google CAA is probably overkill, but again, it was part of the scheme that worked).
The Https Redirect was the last thing to work. Turn it on, try it, and if not working, turn it off, until it does work.
Yeow!