How can I manage inventory syncing for different product variations across two stores?

Hi,

I need some help with the below if someone can help that would be highly appreciated.

I run 2 stores, a D2C and I am currently working on a B2B and would need the inventory to sync across both stores.

The issue I have is the products I sell I only want the D2C site to sell singles, but B2B to only sell in cases.

How do I manage this within Shopify and track my inventory?

Example:

D2C site is selling Widgets at £1 each in singles.

B2B is selling widgets in a pack of 10 for £5.00

I could have 12 in stock, meaning 1 sealed pack and 2 singles. where I want to show the singles are available to buy on the D2C but not on the B2B as it should only show case packed items.