B2B customers have their own Sage A/R customer code, unlike B2C customers which assume a generic Sage A/R customer.
Taxes for B2B are easy as they are controlled by your Sage system. You’ll need to assign the correct tax to your A/R Customers and that information will be replicated into your web store. Any orders placed against that customer will be charged the tax rate assigned to it automatically. The calculated tax amount will appear on the cart and checkout pages.