Consolidating my local and Microsoft accounts

Prior to this thread, was thread Preparing to image my computer, need help

Today, after 3 hours of work, a local consultant was able, by doing a clean install to add to four computers with Microsoft accounts a local account; he also was able to allow 3 of them to talk to each other over a local network; and able to tie in a printer to that network.

What I've been left with are 4 computers, each with two administrators, one a Microsoft account; one a local account. Though I didn't expect this, I'm now finding it essential for two reasons:
1) files may need to be transferred from the former account to the new (local) account.
2) Though I expect the Microsoft account to eventually fade away, right now it is the only way I can do certain things, like establish email communications through the outlook account I was using.
3) It might provide an avenue where I can access/use programs I'm not sure I ever want to use again, to wit: the complete MS 365 Office suite, but I'll see.

Anyway, what I really want to be doing is composing microtonal music--that's what the dedicated DAW computer that I've not been able to get to for months is supposed to be doing. But before the music and before imaging my computers and establishing backup schedules to maintain those machines, I need to get my local account to access and send email, (and I suspect more). So I'm starting a new thread devoted to practical steps I need to take immediately before imaging and backing up those computers.

A lot happened while the local accounts were being established, too much to take in at the time.
Hopefully by bringing up these items now I'll be able to learn more about them later. Unfortunately, I'm not sure I'm expressing myself correctly when referring to them.

1) Each of the local accounts needed to be established under a new user name.
2) None of the local Administrator accounts needed to be tied into an email address. I did, however, need to assign them passwords. Passwords were no problem with the local accounts--they were as related to the prior Microsoft profiles.
3) In order to deal with the previous Microsoft account he needed to know the passwords those accounts were originally assigned. In using only (4 character) PINS I had long forgotten the passwords they'd had originally, He said that the PIN was based on their password and he needed to go deeper than just the PIN. Somehow, by accessing their ip addresses (which he could find out using ipconfig he was able to address those accounts. I will eventually have to provide passwords (and get out of the habit of just using PINS) because, if power goes down, the ip addresses assigned these profile names could change leaving me in the lurch).
4) In the process of doing this work I noticed disk drives appearing that held large amounts of backup data that seemed to eat into my C-drive disk space. None of that data came from any backup program I remembered using. Turned out these drives were created by the built in Microsoft backup program that I might have tried at one time (or that had been created automatically by a Dell Alienware laptop). I don't know if these backups are still being created in the background. I simply deleted the backup data and now have to figure out what to do with that space.
5) I found I had a hard drive that wouldn't mount normally (it made all the right sounds) when I plugged it into the isbn port. It showed up in Disk Management, but I still can't figure out how to have it show up in a disk window.
6) Microsoft Edge brought up a full screen window I couldn't get rid of (before bringing up Task Manager and stopping the Edge process)
7) When it comes to imaging these profiles or backing up information in these profiles I don't know if each profile needs to be addressed separately or as one unit.
8) (Though I was told the Microsoft disk imager was not bad) I think I'm committed to using Macrium as the imager but am not sure which backup program to use.
9) Adding the printer to the local network was difficult because I had the printer connected to one of the computers through a usb connection which he said complicated things. When we switched to an ethernet connection adding the printer was easier.
10) One of the computers was more difficult to add to the network. It can see the other computers but they can't see it. For now it's fine because that is the DAW and I essentially am content having it to myself. But I'd eventually like to look into this.