Steps to map Cognito UserPool as an Identity Provider are given below.
Launch IAM, choose Identity providers from left panel and Click Add Provider button.
Select Provider Type as OpenID Connect Set the following options.
Set Provider URL as follows (Replace italic parts - regionOfUserPool with the current region where you are building this framework. eg us-east-1; CognitoUserPoolId with value from your notepad. ) https://cognito-idp.regionOfUserPool.amazonaws.com/CognitoUserPoolId
Click Get Thumbprint button.
Enter CognitoClient (from notepad) into Audience field.
Click Add provider button.