About the formating look at this thread
Forum Tips and Tricks
What exactly is your problem? I can’t quite get that from your post.
- receiving the event
- parsing the data
- displaying the data
About that particular display there are several threads that show how to get it to work
e.g.
Adafruit SSD1306 [SOLVED]
or
https://community.particle.io/search?q=ssd1306
One thing to not tho’ is that you should not have a delay(15000) in the subscription handler