#debian wiki was a great resource during my last installation. I found these especially useful:

Upgrading stable release to testing
https://wiki.debian.org/DebianTesting

Install Nvidia drivers
https://wiki.debian.org/NvidiaGraphicsDrivers

Enable Prime GPU offloading
https://wiki.debian.org/NVIDIA%20Optimus#Using_NVIDIA_PRIME_Render_Offload

Switch Pulseaudio to Pipewire
https://wiki.debian.org/PipeWire