Where can i find my IAM ARN?

To get the ARN of an IAM user, call the get-user command, or choose the IAM user name in the Users section of the IAM console and then find the User ARN value in the Summary section.

For reference: https://docs.aws.amazon.com/codedeploy/latest/userguide/instances-on-premises-register-instance.html#:~:text=To%20get%20the%20ARN%20of,value%20in%20the%20Summary%20section.