you export it from outlook as an ics file and import that to the calendar.

Sounds easy but unfortunately I do not know how to create an ics file from my outlook calendar or 'import' it into t'bird. Sadly acronyms and jargon are alien to me.

I would think Microsoft would have instructions for operating their mail system somewhere. A Google search brought back this. https://www.techwalla.com/articles/how-to-convert-an-outlook-calendar-to-ics

my calendar is in Outlook 2003 which doesn't look anything like the techwalla pictures. Now what?

orouge said

my calendar is in Outlook 2003 which doesn't look anything like the techwalla pictures. Now what?

I would suggest you ask google. The perhaps unfortunate thing for you is we do not use outlook here, so have not paid for copies. If we had paid copies they would not be for such an ancient version as 2003.

Google and Microsoft would suggest it is not possible see here

but it looks like someone wrote a macro to do it. See http://outlook2ical.sourceforge.net/

Seriously we can not help you get your data out of outlook beyond doing the googling for you. WE simply do not use the product. We can not test the suggestions, nor can we teach you haw to use either outlook or any tool you use to make outlook behave like a useful piece of software.