Salesforce flows - need to send a id in header using flows.

I need to have a solution only using flows no apex classes or triggers.

I am looking for a freelancer with intermediate experience in Salesforce Flows to help me with a project.

Purpose of sending the ID in the header using flows:
- To pass data between systems

Complexity of the data being passed:
- Simple (basic user information)

Ideal skills and experience:
- Intermediate experience in Salesforce Flows


This is a post request and I need to send this user id in the contact record to the api in a header and I am able to send the data using a default value but this has to be a dynamic value that comes from the record