There was an issue with Debian installs a few weeks ago where it broke due to some modules. It can be avoided by using the net installer.
If you’re using an Nvidia card, you will need to download the appropriate drivers. The Debian docs explain the steps, just read carefully to make sure you don’t miss something small.
If you want to make it as seamless as possible, use Debian with Gnome.
Apart from that, there is virtually no difference. You can get and use all the same packages. Games on steam run without issue (or any more than reported by other distributions). I don’t use PPAs but between official debs and flatpak, I haven’t had any issues getting software that I needed.
FWIW I ran: Apex Legends, Resident Evil 1+2, FFXIV, Gears 5, Bomb Rush Cyberfunk and plenty more without a single crash or glitch.
I also switched to Debian from Ubuntu. It wasn’t perfectly smooth but once you get set up, it’s as stable as can be.