This assumes you are familiar with Flow Designer. If not, check out my article FreeKB - ServiceNow - Getting Started with Flows.

At All > Studio, I selected the application. On the Variables tab, I have a string variable named "ear" and environments lab and dev, which are booleans (True or False). 

Then in Flow Designer, I use Get Catalog Variables so that the variables can be used in the Flow.

Then in a subsequent task in the Flow, I can use the variables that were selected in Get Catalog Variables. In this example, the "ear" variable is used.