Recording a call in teams is very simple. During your call, hover over the middle of your screen towards the bottom to get the functions table to appear.

Click on the 3 dots in the middle of the table to display more options.

Click on the "Start recording" button to begin recording the meeting. After the button is clicked it will change to a "Stop recording" button. Click on that button to conclude recording the meeting.

The recording is then processed (which could take awhile) and saved to Microsoft Stream, and then it's ready to play.

The person who started the recording receives an email from Microsoft Stream when the recording is available. It also shows up in the meeting chat—or in the channel, if you’re meeting in a channel.