please can you help? I'm desperate, frustrated and disappointed by jellyfin

[Efficient_Good_5784]

well great: "Error 0x80070666: Cannot install a product when a newer version is installed."
so now I have do redo EVERYTHING ALL OVER AGAIN?!?!?!?!
can anybody understand how or why this JF is frustrating me?!
IF I did it all again - can anyone promise me that it will then FINALLY JUST WORK???

Nobody can promise you that it will "just work". You need to be able to put in the effort and learn for yourself/do things for yourself.
Different things in life require different levels of ability. If you're finding doing things such as this on a computer becomes difficult, it's because you're missing important fundamentals with how to interact with computers and programs.

I'm not trying to be mean here (you can't express emotion/tone through text well). If this software is giving you enough grief were it's negatively affecting your well being, it's probably time you put a pause on using it and evaluate if other software will work better for you.
No one here is going to take 100% responsibility to make sure you get a working Jellyfin server that works to your expectations. We're all volunteers in this space. There was no contract or payment done on either end for anyone to be forced to promise you it will "just work".

Think about it. How are you going to deal with upgrading your server if you can't handle installing it in the first place? Do you want someone to be in charge of handling your server for you?
One of the main principles of self-hosting is that you get 100% control of everything. You gain that freedom.
The pitfall of self-hosting though is that with that level of freedom, you're the one responsible for fixing things and becoming your own 24/7 tech support whenever something goes bad.
The best you can do is ask for help and wait for people to try and help. No one can be forced to guarantee you service unless you entered some form of written agreement for such an arrangement to be done.