I've been using desktop Outlook for about a decade, and updated to 2019 about a year ago. A few months ago I started having multiple issues that I cannot solve:

1. I get asked for my main personal domain email account password SOMETIMES when I start Outlook but not every time. I have removed and readded the account but issue not fixed.

2. I get asked for my comcast email account password SOMETIMEs when I start Outlook but not every time. I have removed and readded the account but issue not fixed.

3. I get asked for my FIVE gmail accounts (side business, civic assoc editor various other gmail accounts that I have). I have turned OFF 2-factor logon and set Outlook in the "less secure app access". I have deleted every gmail account and readded them. I have changed smtp.gmail to smtp.googlemail as suggested on some sites when I've researched this. Some gmail accounts require typed passwords (no cut and paste allowed and my passwords are long and random characters). Some require google app with a random generated number on my phone to authenticate. No rhyme or reason as to which process is used each time.

4. Gmail and comcast emails are IMAP, but often will not download until I physically ask Outlook to download - then I can sometimes get a whole days worth at once.

5. I also have iCloud for Outlook. If I put an appointment in via desktop Outlook, then later EDIT that same appointment on my iPhone, the appointment change is never synced back to Outlook, but sometimes Outlook will then override that change and put it back as it was on my iPhone. This means that I cannot trust my calendar to be accurate.

Sometimes outlook will be acting so wonky (it will freeze for example, or I cannot enlarge it from the taskbar, or I cannot shut it down) that I will have to reboot and I won't get asked for any passwords, and sometimes I will only get asked for one or two. No rhyme or reason.

I have removed and readded all email accounts multiple times over the months.
I have reinstalled Outlook and Office package multiple times over the months.
I have removed and reinstalled iCloud for outlook multiple times over the months. I have used the windows store download version and the apple.com download version. Both have the same issues.
I have logged out/in on iCloud multiple times on my PC over the months (which often creates duplicate contacts and appointments in Outlook).
I have run PST fix multiple times and did error corrections multiple times over the months.
I have tried running Outlook in safe mode with no noticeable difference.

Windows 10 software is current with no outstanding updates.

Nothing I have done or found during extensive online searches into these issues fixes these issues.

Other issues that I have had that may or may not be related: when I reboot - google does not always automatically log back in (I use Edge and Chrome). At reboot a message comes up that Onedrive is not logged in before Onedrive automatically logs in (this only started about a month ago). I will get a notice that my windows account needs to be "fixed" and it just requires me to enter my Pin again. I've also researched this one but the "fixes" don't fix it. My iCloud photos drive on my PC is also never current with the sync with iCloud.com. I have not been able to resolve this either. I also have issue with Chrome and Edge sometimes remembering me and other times not -saying that I am on a new computer. I am not clearing setting when I exit because of this issue, but that did not fix it either. Again, no rhyme or reason. Facebook does the same thing and also does not recognize the code generated by "code generator" on FB on my phone, so I have to force FB to text me a code. This is also a recent thing.

I had to replace my HDD with an SSD about six months ago, and Windows 10 was reinstalled from scratch at that time.

Any help would be greatly appreciated, as I am pretty much at the end of my rope!