Hi CZ,
Thank you for posting, I am here to help you today. Possible reason you are getting this problem is due to a misconfigured default app for handling default web browser settings.
May i know if you are using Outlook personal account or organization / school account?.
Are you getting any error when tying to open the Outlook link mail?.
To fix this try this steps:
Try this right-clicking the link and selecting copy then paste it to any browser manually. Check if this will work.
If did not work try next step: Check and set the default web browser
Go to System preferences then select General. Look for default web browser dropdown and select different browser. Choose to your preferred browser. Once done try again to open the link.
Let me know how this goes. Looking forward to helping you out. If you need more help please feel free to let me know.
Best regards,
Jansher