Add outlook to share option

So, you appear to have Apple Mail setup as an Outlook Account, and there is no Mail item on your Share menu, despite being selected in the System Preferences : Extensions : Share menu items. Usually this is caused by a need to rebuild the launch services database, and afterward, Mail should reappear on your Share menu.

If Share options or Markup is missing…

There is a scrollable command in the above link. Triple-click that scrollable command, and copy/paste into the Terminal application (Dock : Launchpad : Other : Terminal). Press return after you paste it. The next Terminal prompt means the command ran. Now check your Sharing sub-menu to see if Mail is back.

If the above Apple solution didn't work, try the following with the same instructions as above to paste into Terminal.

/System/Library/Frameworks/CoreServices.framework/Versions/A/Frameworks/LaunchServices.framework/Versions/A/Support/lsregister -kill -r -seed -domain local -domain system -domain user

Mail being dimmed is not causing your problem. It is always dimmed because it should always be available.

You cannot choose Microsoft Outlook because Microsoft has not created a sharing extension for Outlook. They did so for OneNote, so they appear to be capable.

If you are using Outlook as your email client and don't have any accounts set up in Mail, I would assume that it wouldn't offer Mail as there would be no way to send anything with Mail.

The Mail extension is not "email". It is actually Mail the app.

You will have to contact Microsoft and ask them to make an extension for Outlook.

Microsoft would have to create a sharing extension.