Note: For Instagram posting you should have Instagram business account and that account should connected with the Facebook page. Also, the authorization process would be handled by Facebook Graph API so, it would be via Facebook only.
Enable Autoposting to Instagram
Check this box, if you want to automatically post your new content to Instagram.
Add accounts
Just click on add accounts and authorize your Instagram account within the script settings. Once you authorize your Instagram account, you will be able to configure your Instagram account within the script settings.
Autopost Posts to Instagram of this user(s)
Select each of the users that you want to automatically post to Instagram when a new post is published.
Instagram Post Image
Here you can upload a default image that will be used for the Instagram post.
