Setting up remote UI with custom domain

SO!
I have spent all my free time the last four days ttrying to figure out how to set my HA OS up with my personal domain. (i bought it for this specific purpose so no, i have no preexisting knowledge here)
I’ve seen tons of letsencrypt+duckdns guides out there. And letsencrypt has been mentioned to be a decent solution for what i’m trying to do.
I have also played around with using cloudflare proxy and SSL, but also with no success.
I even tried to set up a tunnel with the cloudflared add-on. But even though the tunnel appeared on my CF dashboard, Link never worked.
My current workaround is to simply redirect my personal domain, to a Nabu Case URL. Bc saving it is not an option… Any device i might be able to save it on, and carry it with me, will also be able to either go local or use the app. So sure, NC is easy and works. But the functionality is shit if i have to magicly remember that on a device not belonging to me.

So the dream of custom domain lives on. Ofc this may be a portforwarding issue, since i’m forced to use my ISP’s OS for their router. -Might just ask them to completely disable any firewall of theirs on my connection, and then just set up an easier to manage router.
But even so, I have no clue wether my port forwards and firewall bypass are failing, or if i just set it up wrong.

I won’t give an example of what i have tried, since it’s basicly the entire first page of any imagineable google search on the topic. :b

Has anyone that has the patience to help, succesfully set this up for them selves?
-and if so, how? EXACTLY HOW!? Not ‘‘do this and then that’’. Not a video guide that skips anything related to tokens and adresses i shouldn’t share with others. (why not just use ‘thiswouldbeanip’ for the example?)
But a step by step guide, from start to finish.
Or even just a guide for doing it completely insecure idgaf. That partial success would be enough at this point xD

Oh and how does one go about creating or just storing CSR on HA?
Most my attempts at encryption have died right there.

The simplest approach is to use the LetsEncrypt add-on, which should have sufficient documentation, assuming of course that you have a static IP address.

If you don’t then you’ll need a combination of:

  1. DuckDNS hostname and integration
  2. Your own hostname as a CNAME of your DuckDNS hostname
  3. The LetsEncrypt add-on for your hostname

Well i did set it to a static ip. But I’m still Waiting for assistance from my ISP with the ports.
Like, :8123 should be my server Right? Or at least be seen by canyouseeme.org.

If you forwarded port 8123 on the router to port 8123 on the HA hosts’s IP address.