How to pull links to promotions in the Bitrix CMS in the elements to which these promotions are linked?

Question

1C-Bitrix

Good afternoon.
Please help a newbie in Bitrix solve one problem.
There is a website for a construction company. Promotions have been created there, and apartments for which this promotion is valid are attached to each promotion. The customer asks to make sure that when entering the page with a list of all apartments in the residential complex, there is
a clickable label "Promotion" on the layouts. Those. this label should contain a link to the promotion to which the specific layout is linked.
I can't figure out how to pull the link to the promotion to which the layout is attached. When viewing an element array, this link does not appear anywhere.
Prompt, please, the decision who faced it. Thank you.

Answer 1

Judging by the description, this is not a difficult task, since your promotions are created by sections / elements of the info block.
1) Understand their structure and how the connection between the promotion and the product is put in the admin panel.
2) Read about infoblocks and API
3) Write a script :)