Looking for Advice on Linux Security and Privacy? Feel Free to Ask

My main reason for not to switching Linux is gaming. I have games with mods, like World of Warcraft, Cyberpunk, Fallout, etc. I have also a trainer called Aurora which I am running on single player games. I have a very large Steam / GoG library, and some games like Helldivers 2 have DRMs. Apart from games, I prefer to use OpenSUSE but some major VPNs like Mullvad have no official packages for it. How to solve it? For Proton, it is asking 4 times for root password when connecting to a VPN server, why is that and how to prevent it? For security, can I use biometrics / PIN to login OpenSUSE like Windows Hello? I am against typing my own password everytime I login to an OS. Are there any hardening guides or scripts for OpenSUSE like Microsoft’s Security Baselines? I have experience on SUSE Enterprise Linux Server, but not on personal level with GUI.