How to migrate from GMail

I've had my GMail account for what must be almost 20 years now, and it's pretty ingrained in my life. My mortgage info comes via GMail, my bank statements come via GMail, my health insurance comes via GMail, etc.

Thinking about migrating honestly seems like an insurmountable task. I have no idea where to begin. How the hell do I go about untangling GMail services from my life.

I've potentially been looking to move to Proton for email, but any other suggestions (preferably European based) would be welcome.