Pulling in an external json/xml data INTO WordPress self-hosted site

I’m looking for some documentation on how I can pull xml/json data from a non-wordpress website into a self-hosted wordpress site.

Googling around seems to be innundated with how to move WordPress data but few that gets into details on how to integrate INTO a wordpress website. Most of those seems to be skipping basic info and get into details that don’t make a lot of obvious sense to me yet.

Notes: first time api user here. I get the basic idea. I just don’t know how to get WordPress to format the info from an external site.

The site I am pulling from is https://www.zoho.com/projects/developers/projects-api.html if that helps.