Can I send and receive email using the apple mail with an icloud custom email?

I need to create a new email account. I've read the info on adding a custom domain email. All fine, except I'm a little fuzzy about how to see and read and respond to the emails. Is it possible to add a custom domain name ie Example@example.com onto Apple Mail, as you would adding Gmail? or an email from a website? Or must I sign into icloud.com/mail to see the mail? Seems a little wonky.

Before I go through the hurdles and hoops and verifications and MX records and updating and verifications and are you sures and confirms, is this possible? Otherwise, I will continue to deal with trying to get all that accomplished by adding the email account I have just set up with the hosting provider and it's free email account (which I haven't been able to get to work yet, which is typical with Apple Mail; in the end, I've been able to add 3rd party but it's always been a struggle...)

And, so, through frustration with that process that I struggled with for about two hours yesterday, I thought maybe the icloud+ custom domain email is the answer.

However, if that isn't possiblle, this follow up: But I do understand if I want to "just simply" add name@icloud.com that this can be added to Apple Mail, correct?