In this page we can see 3 tables synced from Webflow, Products, SKUs and Categories.
In the SKUs table I have added a new column of type Number for the new quantity and a new column of type Button configured with the Update Inventory action. You can right click to see how the action is configured.
Some ideas:
Build a dashboard with your current inventory value. Use automations to let you know when the quantity of an item is below a certain number. Add an additional number property for each SKU for the cost of each item and keep track of your margins.