Mullvad gets blocked often so you may run into issues with streaming services, financial sites etc. for that reason, I would recommend Proton VPN. You can sign up with a free account--don't provide a phone number or recovery email--you can use their recommended recover phrase instead--then upgrade to a paid account so you can use btc. If you start with a paid account they require credit or debit card.
Discussion
If you want to separate your vpn from proton's all-in-one service, then just go with the VPN. I can provide more steps to use their other services to get you away from google mail/drive etc if necessary :)
Also would love to move away from Gmail/drive in the future but atm use it for business services too so I would need to be able to access it. Iām looking into getting a separate cellphone to use as a de-googled device (my daily cell is an iPhone).
Cool cool, yeah... GrapheneOS all the way.