Is there any functionality in magento 2 that will force the user to register when passing the checkout. If the user does not have an account, do not allow him to buy
You need to disable guest checkout, customers must then create an account to place an order.
To disable guest checkout: In the Sales section in the left panel, choose Checkout. Expand the Checkout Options section. If necessary, clear the Use system value checkbox. If the setting is for a specific store view, choose the store view where the configuration applies.