Super mega noob jellyfin remote access

[G1r6]

I want to build a server for Jellyfin streaming and for saving data from my family (just pictures and videos).
My plan was to buy a mini PC, but I just don't know how I can access Jellyfin from an outside network. 
I am testing Jellyfin on my main PC to see how it would works, but I just can't find a good tutorial or something. 

I tried using:

Cloudflare
Caddy
DuckDNS
Adding ports in firewall and router


The tutorials on YouTube I followed just never worked for me. Please help me; I am frustrated.

[TheDreadPirate]

Some ISPs have all their subscribers behind a CGNAT, making self-hosting at home hard or impossible. Who is your ISP, if you don't mind my asking?

[G1r6]

I live in germany. My ISP is 1&1 and next month i am switching to o2.
Dont know if this means anything to you. Right now i have an old FritzBox 7412
but i get a new one with my new provider.

[TheDreadPirate]

I can't find anything indicating your current ISP is using CGNAT (good thing).

Let's keep things simple for testing purposes. Skip the reverse proxies and cloudflare for now. Open port 8096 on your router, point it at your jellyfin server's LAN IP.

On your smart phone turn off WiFi. Open the jellyfin app and type http://WANIP:8096 and your credentials.

[G1r6]

It didn't work at all. In the Jellyfin app, there wasn't even a loading symbol, it just stopped instantly.

btw would it be easier to establish an external connection if I had a NAS system like Synology or QNAP?

[TheDreadPirate]

It didn't work at all. In the Jellyfin app, there wasn't even a loading symbol, it just stopped instantly.

So it connects, you can login, but you can't watch anything?  Can you share you logs from this attempt?

btw would it be easier to establish an external connection if I had a NAS system like Synology or QNAP?

No.