Just use iCloud. It allows you to setup custom domains no worries and give emails to everyone who’s included into your family plan. I’ve got two custom domains setup that I share with my wife.
Alternatively you can use Fastmail but I recentely moved from it to iCloud for consolidation purposes. Don’t get me wrong, Fastmail is absolutely awesome and I had great experience, I just wanted to consolidate.
Don't have any apple devices, not sure if i even can.
For you it is Fastmail then, they are awesome and integrate with 1Password for an-email-per-service thing (known as Hide My Email in Apple's world)