Just got an email from proton today about their “lifetime deal” for proton pass I currently use bitwarden and Firefox relay but I’ve been debating trying to drop my Gmail account and switch everything to my proton account. Thinking it would be silly to pay Firefox $12 a year just for relay when I can get that and more from proton for the same price.

All of that to say how exactly does the email alias work and can I set a custom email subdomain to just have an alias get created whenever an email is sent to the email I give someone without me having to go manually create it?

Why not simplelogin integration in Bitwarden? The first comes as part of your assuming proton unlimited package