This may help.
In battery options put all apps to be always unactive.
In my case, I only have Whatsapp, youtube and zoom, in “never unactive mode” because those I use the most.
Also disable find my phone of samsung, and sending marketing in the background, cant remember exactly where, but we send information to samsung and google in the background.
I have also turned off “Hey google” function, i guess it hears me all day and that may drain.
Of course use 60hz and not sure if in s23fe you can change screen resolution.
I have a A54 and I’m having like 6:30 SOT and 8h screen off time.
Let me know if some of this was useful
Buy a S23 Ultra it has the best screen on time, more than 10 hours.
Later I will post recomnendations for batery life.