How to organize communication between infoblocks?

Question

1C-Bitrix

How to organize communication between infoblocks?
In the first infoblock, you need to store the name of the event, the number of tickets, the number of sold, the number of ordered.
In the second infoblock, you need to store a unique ticket ID, paid / not paid, and a "link" (or as it is called in Bitrix) to the first infoblock, so that when editing / creating an infoblock element (in the admin panel), you can select an element from the drop-down list from the first block.
This is the first time I've encountered Bitrix.

Answer 1

Property ib - Binding to elements ib. If you have a type of store, then probably also indicate in the settings that these are trade offers.
ps
But advice for the future, for super third-party functionality, do not use these infoblocks at all, they are only suitable for simple news, and out of desperation they are used for a product catalog.

Answer 2

Do not spin the bike, use the regular functionality.
Trade offers SKU Warehouses are more than enough to implement the plan