Implement functionality for the site on Bitrix

Good afternoon!

Site on Bitrix (the latest version). A ready-made solution is installed on the site and modified chel.foodim.ru/

The solution page on the Marketplace marketplace.1c-bitrix.ru/...

You need to make a product/functionality combo set.

An example of implementing the functionality of a competitor:
dodopizza.ru/chelyabinsk/...

From you terms and cost (for full work).