As the OP states you can get a registrar to host a domain for you and then you create a subdomain anywhere you fancy and that includes at home. Do get the glue records right and do use dig to work out what is happening.
Now with a domain under your own control, you can use CNAME records in other zones to point at your zones and if you have dynamic DNS support on your zones (RFC 2136) then you can now support ACME ie Lets Encrypt and Zerossl and co.
Sadly certbot doesn't do (or it didn't) CNAME redirects for ACME. However, acme.sh and simple-acme do and both are absolutely rock solid. Both of those projects are used by a lot of people and well trod.
acme.sh is ideal for unix gear and if you follow this blokes method of installation: https://pieterbakker.com/acme-sh-installation-guide-2025/ usefully centralised.
simple-acme is for Windows. It has loads of add on scripts to deal with scenarios. Those scripts seem to be deprecated but work rather well. Quite a lot of magic here that an old school Linux sysadmin is glad of.
PowerDNS auth server supports dynamic DNS and you can filter access by IP and TSIG-KEY, per zone and/or globally.
Join the dots.
[EDIT: Speling, conjunction switch]
Break out a piece of mail, connect the dots, and you see their eyes light up with comprehension. "Oh, so that's how my computer gets to google.com; it's just like how my postman knows where to deliver my mail!" Then a critical component is demystified, and they want to learn more.
Running a DNS server is honestly such a good activity for folks in general.
Which brings me to a rather big gripe about other resolvers not respecting TTL, 70% of https://www.whatsmydns.net/ reported it could not query A names, while 30% were like "Yeah here you go" from their cache.
I fixed the glue and got everything back up, I need to write an automated script to check every day if my IP has changed and alert me to update my glue record at my registar.
I use a lot of mix and match scripts to maintain other aspects like challenges for DNS e.g. Letsencrypt, I'll use their hooks to update my DNS, resign it (DNSSEC), complete the challenge, then cleanup. My more personal domains I don't use DNSSEC so I just skip right ahead.
I quite enjoy handling my own DNS records, BIND has been really good to me and I love their `view "external"` and `view "internal"` scopes so I can give the world my authoritative records, and internally serve my intranet and other services like pihole (which sits behind BIND)
Better yet, set up ssh to the proxmox server and ask claude code to set it up for you, works like a charm! claude can call ssh and dig and verify that your dns chains work, it can test your firewall and ports (basically running pen tests against yourself..), it can sort out almost any issue (I had intel wifi card and had firmware locks on broadcasting in 5GHZ spectrum in AP Mode - mediatek doesn't - claude helped try to override firmware in kernel but intel firmware won't budge). It can setup automatic nightly updates that are safe, it can help you setup recovery/backup plans (which runs before updates), it can automate certain proxmox tasks (periodic snapshotting of vm's) and best of all, it can document the entire infrastructure comprehensively each time I make changes to it.
Multiple comments in this thread refer to TLS certificates
Why is payment to and/or permission from a third party "necessary" to encrypt data in transit over the a computer network, whether it's a LAN or an internet. What does this phoney "requirement" achieve
For example, why is it "necessary" to purchase a domain name registration from an "ICANN-approved" registrar in order to use a TLS certificate
Is obtaining a domain name registration from an "ICANN-approved" registrar proof of identity for purposes of "authentication". What purpose does _purchasing_ a registration serve. For example, similar to "free" Let's Encrypt certificates, domain names could also be "free"
Whatever "authentication" ICANN and its "approved" registries and registrars are doing, e.g., none, is it possible someone else could do it better using a different approach
This comment is not asking for answers to these questions; the question are rhetorical. Of course the questions may trigger defensive replies; everyone is entitled to an opinion and opinions may differ
Last few days I've been migrating everything to luadns format, stored in github and then I have github actions triggering a script to convert it to octodns and apply it.
I could have just used either, but I like the luadns format but didn't want to be stuck using them as a provider
Unless of course you will invest 5-6 figures worth of US dollars worth of equipment, which by then you can look back and ask yourself, was I better off with Google Cloud DNS, AWS Route 53 and the likes.
(disclaimer: I contribute a tiny bit to dnsdist.)
gawd just install webmin ffs