Correct me if I'm wrong, but what you're describing is client-hosted Bedrock servers, not a persistent, always available, self-hosted server. AFAIK connecting to a friend's world in Bedrock is free, but they must also be online. Hosting a persistent Bedrock server is a paid feature (Realms).
Additionally, highlighting that Bedrock Minecraft is not supported on Mac.
There are surely other ways of enabling multiplayer Minecraft for a family than what I've described, but this is the way I'd recommend.
Correct. There are ways to host bedrock servers, it just isn't as easy and most people are better served by realms.
Also, I thought you could play the iOS version on Mac. Doesn't apple let you run iPad apps on macOS?
Unfortunately, Apple made the decision to have that be an opt-in flag for developers, and so the vast, vast majority of iPad apps don't allow themselves to be used on macOS.