01

Go To https://api.stackexchange.com/

Go to All Documentation to see all the enpoints you can get

02

Scroll down and click on questions link

03

You can paste an api endpoint as a url to see the JSON

/2.3/questions?order=desc&sort=activity&site=stackoverflow

If you click it on this page, it will open in a new tab

04

Notice that the json uses the enpoint with the beginning URL

https://api.stackexchange.com/

then

2.3/questions?order=desc&sort=activity&site=stackoverflow

05

Use Postman at https://www.postman.com/

Click get started and paste in the FULL endponit

https://api.stackexchange.com/2.3/questions?order=desc&sort=activity&site=stackoverflow

You can get the app on your computer but just use site for now