I bought a used Note 9 and installed /e/ on it. This was not without problems. So I want to give help to others, who want to use /e/ on an SM-N960F/DS.
My Note 9 had the newest firmware, Android Q / 10
I give some links, where you can find instructions. Because, why should I do the same, someone else did before me?
First, which buttons are needed, to boot to recovery mode, download mode?
Second, how to install TWRP, get root access and stop encryption
this second article is maybe helpful
Sometimes it is not possible to install TWRP through Odin, here is the solution (so it was for me)
Hope this can be helpful.