Copy the .jar file into the "Applications" or "Gallery" folder on your phone.

Because the Nokia 7230 runs on the software platform, it does not support modern smartphone apps like the official Facebook app for Android or iOS. Instead, you can access Facebook through these legacy methods:

Mobile web via built-in browser or Opera Mini

While I can’t browse live articles for you, I can reconstruct what made that experience unique, based on the technology of the time. Here’s an “interesting piece” written in the style of a nostalgic tech blog.