Need Help Seting up Hardware Acceleration

[Jelly1991]

Set up:
Windows 10 x64 as server
Nvidia RTX 2080 Ti

Monitor: LG C3

Soundbar: Samsung 990D (eARC to TV)


Question 1:
I am setting up hardware accelration with Nvidia NVENC in 'Transcoding', but not sure if i am ticking all the right options applying to me?
   

This is what nvidia showing my graphics card supports for decoding
       


Question 2:
What setting should I use to play Dolby atmos audio on my soundbar? When I look at the dashboard, the audio is always showing TrueHD 7.1 but its transcoding. Am I getting the full potential of this? Thanks.