Enabling Kanban board in views is a new feature in Dynamics 365 CE. Those who practice lean or agile methodologies in any industry would love to use this feature in Dynamics 365. Please note that this can be enabled only in Unified Configuration Interface and not in legacy forms.
Steps to follow:
- Create a new solution or open and existing solution and add ‘Activity’ entity.

2. Select ‘Controls’ tab and click on ‘Add Control’ link

3. From the list of controls, select ‘Kanban’ and click on ‘Add’

4. Select ‘Web’, ‘Phone’ and ‘Tablet’ and click on Save

5. Save the entity and publish
6. Now you can see that the Kanban view control is enabled in Activities views.

7. And opening in Teams, it looks really good.

You can also the classic ‘Read Only’ grid by selecting the option from the command bar also.
Show As> Read Only grid

Hope this helps!