You are in for a rough go. There is no modern software that will open that file including later versions of Pagemaker or InDesign.
Someone may stumble on this, but I wouldn’t hold out much hope.
I observe that Convert InDesign, Publisher, Quark or Down-Save InDesign CS5 to CS3 offers a per-document fee based conversion service. It doesn't mention PageMaker specifically but the company did used to market PageMaker conversion tools. Could be worth contacting them.
The PM3 converter is still available in the Adobe archives - Adobe - PageMaker : For Windows : PageMaker 3.x Converter for Windows
Full details are given about how to do it, assuming you have a more recent version of PM to open it.
The usual problem with opening very old PM files is that any linked images will be missing. Missing fonts can be substituted and tracking &c. re-set to make the page look authentic.
Thanks. I tried downloading and running the PageMaker conversion program from version 3 to 4 but it won't work since both of my laptops are 64-bit and it said I should download the 32-bit version which I can't find anywhere. Then, I don't have a newer version of PageMaker to read a vers 4 file anyways. I have access to MS Office suite of software as well as WordPerfect Corel suite and Adobe InDesign, Dreamweaver, etc. but do not have anything that can read a PageMaker 3 file. So I guess I'm totally dead on this project unless someone has kept up with versions of PageMaker and can take my file and read it. Thanks for your help though. Appreciate the response.
"Freedom has a taste, and for those who have fought for it,
the taste is so sweet the protected will never know."
Author: General George S. Patton
I'll see if I can find someone via twitter but don't count on anything.