Dynamic Content refers to the data generated by triggers and actions within a flow. This data can be used in subsequent steps to create dynamic workflows. You can insert dynamic content into fields by selecting it from the Dynamic Content panel, allowing you to customize actions based on the input data, such as including details from a SharePoint item in an email notification. This makes your flows more responsive and tailored to specific scenarios.
In Power Automate, you can create variables to store and manipulate data within your flow. These variables will appear under the Dynamic Content panel, allowing you to use them in subsequent actions. This makes it easy to reference and utilize the stored data throughout your workflow, enhancing the flexibility and functionality of your flow.
I cannot help you more than that, since I don't know what you're trying to accomplish with your expressions. Since you say that it "literally types out "@{body('Parse_RETURN_JSON')?['orderId']", that would indicate that you did not use the expression builder to create the expression.
You will need to show the action and how it is configured rather than the flow run history in order to figure out your issue.
