How should I change my operating system to a different one or newer version without creating a new Linode?

All I want to do is move from Debian 10 to 11, or possibly migrate to Ubuntu 22.04. I would like to do this without losing my IP address, and while maintaining my SSL certificates that I installed through certbot-apache.

You can do this in place. For Ubuntu, it's pretty easy:

https://fossbytes.com/upgrade-ubuntu-using-command-line-terminal/

For Debian, it's more complex:

https://www.linode.com/docs/guides/upgrade-debian-to-the-newest-release/

Remember, backups are your friends…

Also, if I want the latest version of the letsencrypt certificate, I noticed I need to use the snap package for that. I did this on another Linode that I'm running Ubuntu 22.04 on. On my Debian Linode I used the python3-certbot-apache package in the repos. If I just copy paste everything to a new Linode running Ubuntu 22, will I have compatibility issues?

Since Ubuntu is Debian's downstream child, most likely anything you can do on Debian will work on Ubuntu. I'd avoid snap packages like the plague. Although snapd is available on most distros, Ubuntu is the only one that actively uses/promotes it. Once you put them in place, you're locked in to Ubuntu.

Alternatively, you can set up a new Linode, install whatever distro and configure it the way you like and then swap the (IPv4 only) addresses. If you use IPv6, you're going to have to change all the apps that may depend on the IPv6 address (e.g. firewalls) to use the new address your new Linode will get. There's no way to avoid this.

-- sw

Since Ubuntu is Debian's downstream child, most likely anything you can do on Debian will work on Ubuntu. I'd avoid snap packages like the plague. Although snapd is available on most distros, Ubuntu is the only one that actively uses/promotes it. Once you put them in place, you're locked in to Ubuntu.

I agree with you on this. I was encouraged to use the snap version of certbot by the LetsEncrypt community forum members. If I do go with Debian or another distro, do you think I should use another certificate provider like the one I got when I bought the domain from namecheap? I never used it because the certbot process was easier to configure.

Thank you for your detailed answer.
Much appreciated.

If I do go with Debian or another distro, do you think I should use another certificate provider like the one I got when I bought the domain from namecheap?

Just keep using LetsEncrypt. certbot-apache is available on Debian. So is certbot. They work the same way as on Ubuntu. You shouldn't have to change anything about how you use them…only (possibly) the configurations they use.

-- sw

I was encouraged to use the snap version of certbot by the LetsEncrypt community forum members.

They may have had out of date info. The previous Debian version (10) had a really old version of certbot, and so you were better off using snap. But Debian 11 has a relatively up to date certbot and you will be fine just pulling it in like any other package. I’m doing that with my Linode, running Debian 11, with the standard certbot package, and the python3-certbot-linode-dns plug-in, which you will only need if you’re doing wildcard certificates.