Hi @Belgana_France,
Welcome to Airtable, and to our Community forum! It sounds like Airtable will lend itself well to what you’re hoping to do with the overall structure of your base.
Looks like you’ll need at least a few tables – product, bundle, and inventory. I’ll provide some very basic screenshots to show examples of how this could be built. The product table would include records for each chair (or other products) and the fields would include information like the SKU:

The bundle table would include information about each bundle, including which products will be in them:

The inventory would function as an inventory log, with records that show each incoming and outgoing change, like restocks and shipments to customers:

You can see that the tables are linked via linked record fields. Also, two different rollup fields are used (1) to pull the current inventory of each item from the inventory table to the product table (using the SUM(values) function):

and (2) to show how many of the products in the bundle are in stock in the bundle table (using a conditional statement and the COUNT(values) function):

There is currently no way to have a linked record field use a condition to determine which records get linked (links must be made manually), but perhaps you could add a formula field to the bundle table to indicate whether or not you need to use a “backup” bundle:

This formula configuration is limited, as it’s based on every bundle having two products (check out the formula field reference).
There are many ways to configure a base for your use case, and my suggestions are just meant to be starting points. At the very least, I hope this gives you some ideas about how to get on track with using Airtable. If you come up with a better solution that works for you, we encourage you to share on the forum!
Also, check out our Getting started guide and webinars to learn more about Airtable.