How to customize the types of notifications from Worksection to Slack?


As with the user, detailed notification settings can be found in the member's card in the People section. 


Go to the Slack user profile and adjust all the necessary notification settings1.
Here you can also enable Auto-add to all new projects2 and Auto-subscribe to all new tasks3 (this means that at the stage of creating a task, the Slack user will be automatically proposed to the list of subscribers).