On the "Insert template content" step you can choose the necessary template type, insert and edit the content. Press Next to proceed.
For more details on the Stack Template structure and general rules, please see our Maestro Stacks Guide, Section "2. Maestro Stack Template Structure". For more information about AWS CloudFormation, see AWS Utilization Guide, section 6.1. AWS CloudFormation Template Introduction. For more details about Terraform, please see the Services Guide, Terraform as a Service section.