post https://marketplace.walmartapis.com/v3/ca/fulfillment/inbound-shipments
Once you’ve converted items to WFS, you are ready to start shipping items inbound to Walmart.
To do this, submit an inbound shipment request. The inbound shipment details when you expect to ship the product, as well as the items and quantities being shipped.
Each shipment sent to WFS should have a corresponding inbound shipment.