Parsing and using JSON is one of the fundamental components of the Modern Web. Now your Atari can do it with the help of FujiNet and the N: (network) device! Of course there is a excellent video which will break this down for you in a few moments:
The N: is new, and as such it’s documented over at the FujiNet wiki and it worth a read:
The N: device gives you access to a whole slate of modern web protocols in Atari Basic!