Start9 is very simple for the fact that you already have everything ready to download.
There are even more user-friendly options like Umbrell, but it's not too focused on privacy.
If you want to learn the whole process you can start with a raspberry pi4 or 5, although it won't be a big change either. Anyway if you want to do it all yourself, I recommend you take a look at these two websites:
https://darthcoin.substack.com/p/bitcoin-private-banks-over-lightning
https://minibolt.minibolt.info/bonus-guides/bitcoin
If you have any question just ask. I will be glad to help you :)