Developer's Globe
#bitrix24
Video course - https://helpdesk.bitrix24.com/courses/index.php
REST API Guide - https://training.bitrix24.com/rest_help/
Bitrix24 Bot Platform - https://training.bitrix24.com/support/training/course/index.php
Bitrix24.Market - https://www.bitrix24.com/apps/dev.php

All Bitrix24 documentation - https://helpdesk.bitrix24.com/documentation.php