Explanation
Box 1: Yes
Once an outgoing webhook is added to a team, it acts like bot, listening in channels for messages using
@mention, sending notifications to external web services, and responding with rich messages that can include cards and images.
Box 2: Yes
Webhooks are a great way for Teams to integrate with external apps. A webhook is essentially a POST request sent to a callback URL. In Teams, outgoing webhooks provide a simple way to allow users to send messages to your web service without having to go through the full process of creating bots via the Microsoft Bot Framework. Outgoing webhooks post data from Teams to any chosen service capable of accepting a JSON payload.
Box 3: Yes
Create an outgoing webhook
* Select the appropriate team and select Manage team from the (* * * ) drop-down menu.
* Choose the Apps tab from the navigation bar.
* From the window's lower right corner select Create an outgoing webhook.
* In the resulting popup window complete the required fields:
* Name - The webhook title and @mention tap.
* Callback URL - The HTTPS endpoint that accepts JSON payloads and will receive POST requests from Teams.
Reference:
https://docs.microsoft.com/en-us/microsoftteams/platform/webhooks-and-connectors/how-to/add-outgoing-webh
