Thank you for reaching out to the Community. As of this moment, running a delivery stock report in QuickBooks Online is not possible. However, there are similar reports you can check what's in stock using these reports.
Inventory Valuation Summary: The quantity on hand, value, and the average cost for each product.
Inventory Valuation Detail: Your transactions for each inventory item, and how they affect quantity on hand, value, and cost.
Physical Inventory Worksheet: Your inventory items with space to enter your physical count, so you can compare to the quantity on hand in QuickBooks.