Accessing my Gmail via MS Outlook on my MacBook Pro

Neither gmail nor Outlook are Apple products. Gmail is Google; Outlook is Microsoft.

There me be a user here who has knowledge of your specific issue, but he/she may not check in any time soon as we're all volunteers.

You will be better served by asking the developers of the apps your questions and seeking their help with your issues.

They are responsible for making their apps work with macOS, not the other way around. But I can certainly understand the dilemma working with them both.

You're running an old version of macOS and probably an older version of Outlook. Google/Gmail doesn't support some older setups, though I don't know exactly what the cutoff is. You'd need to ask Google. However, I suspect that's the problem. It's not Apple's fault. It's not Microsoft's fault. And really, it's not Google's fault. They decided that older software was too great a security risk.

I'm running Ventura and the latest version of Outlook. All I had to do to add my Gmail account to Outlook was to tap the button in the upper left corner of the window, select "Add Account", type in my Gmail address and, when I was re-directed to the Google page, select my account and agree to the terms. Because I am already logged into Google from this browser, I didn't even need to enter a password.