How can I access my text messages online so I can print them for court?

You either take screenshots in sections and print them from the photos app, which is very cumbersome, or you use a computer app like PhoneView or TouchCopy to import them to a computerized as a pdf or text file and print them that way.

https://www.ecamm.com/mac/phoneview/ - Mac Only.

https://www.wideanglesoftware.com/touchcopy/ PC or Mac.

You’re welcome. Good luck.