They look similar but a VGA port has 15 pins and a serial port has only 9. Serial ports like this one were really common before USB was used. You would plug peripherals into it kind of the same way you use a USB port. Mice were probably the most common use, but you could plug a lot of different things into them.
You might have trouble getting free unrestricted library cards if you don’t live in the area that the library serves. They are usually paid for with taxes and aren’t there to serve people outside their community.
If you’re willing to pay for it, I know that the Ottawa Public Library in Canada offers membership for $90/year to people living outside Ottawa. You may find something similar at other libraries.
The Libraries and Archives of Canada will issue a card too, but you have to visit the archives in person and have a reason you are using the archives and not another library.