Organization ID is required in the authentication process to get your organization details.
Follow the below steps to find the OrgID from your organization account:
Step 1: Visit https://admin.atlassian.com
Step 2: If you have access to more than one Organization accounts, select the one which you want to know the Org Id.
Step 3: Check the URL from the address bar and collect your OrgID.
Example
If your address bar has:
https://admin.atlassian.com/o/152d61b6-****-****-****-********b640/window
Your OrgID is: 152d61b6-****-****-****-********b640