Convert PDF to PDFA using ConvertAPI

Who is this for? For developers and organizations that need to convert PDF files to PDFA for long term archiving. What problem is this workflow solving? The file format conversion problem. What this workflow does Downloads the PDF file from the web. Converts the PDF file to PDFA. Stores the PDFA file in the local file system. How to customize this workflow to your needs Open the HTTP Request node. Adjust the URL parameter (all endpoints can be found here). Use your API Token for authentication. Pass the token in the Authorization header as a Bearer token. You can manage your API Tokens in the User panel → Authentication. Optionally, additional Body Parameters can be added for the converter.

Help me set up the n8n workflow "Convert PDF to PDFA using ConvertAPI" (https://n8n.io/workflows/2317). It uses: HTTP Request. Import the template JSON into my n8n instance, list every credential I need to create, and walk me through testing it.