Starting a new PBI Cloud setup with 2-3 users

I've been working with PBI for years, but it's always been in environments where either an IT administrator set up everything, or I set up a Cloud account with PBI Pro just for myself.     Here's my situation:

1) I want to have a PBI setup for my employer: specifically for my boss, myself, and one other developer

2) We don't have any Microsoft accounts  set up at all   (we don't use Teams or Office, we are more of a Google shop, but we still use MS SQL for database work)

3) My understanding is that we could have  3 PBI Pro accounts (for $10.95/month/user) , where one other developer and myself could push up content to a common workspace, and have our boss interact with the results in the cloud  (and possibly create some content as well)

4) When I did this myself, I had have a "KevinGoffOnMicrosoft.com" account, which I created so long ago, I don't even recall how I created it.

5) When I try to start this for my company, I can't get out of the box because the email I specified isn't a Microsoft account.  

6)  So here's my question:  given my email is [email protected]   (and the other two are their names, same domain), how specifically do I get started in creating a workspace and then adding the 2 other people as users?

7) Also, I had thought the cost for this was going to be roughly $33/month for the three of us.   Is there also a charge for any kind of O365/Azure service?     That was the other part I wasn't sure about: whether we could have what I described (common access to workspaces, where I could also set up a gateway for DB refreshes) for $33 a month  (realizing the 1 GB limit), or if there would be other costs.

Sorry for asking a basic question - I've been creating content in PBI for years, just haven't tried to do a multi-person setup yet!)

Thanks in advance,

Kevin