If the meeting has already been created or started in the chat channel, you will see a "Join" button at the top right.
Click this button to join the meeting.
Below is an example of how this looks in the Teams chat window (see Figure 1).
Figure 1. Joining a meeting from chat
Note:
When joining from the chat, your audio and video settings will be the same as those set before joining. If necessary, you can adjust them during the meeting.
