Custom domains in email

Hello, I’m looking to compartimentalize my email, and have a few doubts about using custom domains. In the first place, I think that they are a great option for keeping control of the address and be able to change providers. I would only use them in websites that I deem important or that already have my name. But I don’t know how to use them in practice. For example, I thought of buying a domain that contains my name to be able to use it in professional environments, but I don’t know if it’s appropiate to use the same domain for banking and personal stuff, to not mix professional and personal identities. Maybe using subdomains is a good option?
Any advice is appreciated. Thanks!

Use your name.surname@owndomain.com for legal stuff, like banks, governments, financial services which already have access to your real data. For the rest use alias service like Anonaddy or SimpleLogin. Use one alias per website, don’t use the same alias for multiple sites. If your alias domains gets blocked, buy your own domain from sites which are privacy friendly, like njal.la and use it for your aliases.