So this part 2 of the setup is not mandatory, but will help you change some preferences and look/feel of the integration. The settings area will also give you direct access to the chat bot, and I will explain more about that later.
Open the Dynamics 365 app in Teams
In settings you choose what environment you are showing, and the app. The App has to be UI app for it to show. Because this user might not need full access via Teams, maybe you should consider making a smaller app just for Teams.
The last setup you can do is connecting the BOT to your data.
Now it is possible for the chatbot to read and work with data in Dynamics.