I have a POST webhook set up on local machine. How can I get it so I can pass body data as JSON to the webhook and then use that data in another node? Much thanks.
Actually, as soon as you have created the Webhook-Node and saved the workflow you are able to do exactly that. Nothing else needed.
So not sure how to help you exactly. The best is probably to check out these tutorial videos. They go over the basics of n8n and also show how the Webhook-Node works. I am sure after you did watch them you know exactly what to do.