Step 1:

Open the postman select any request and you will see the {{baseUrl}} variable listed as part of request URL .

Step 2:

Click on the Collection and Select Variables tab, to add or update the variable value. The {{baseUrl}} variable value must be set to the environment under test. Then click on Save.

Step 3:

Click on the Share button. This will popup a share window.

Step 4:

Click on Via JSON link tab and then copy the URL.