Stay on top of things
Notifications let you know when someone @mentions you, likes something you’ve posted, or replies to a thread you started. The Activity feed helps you stay on top of all your notifications.
Click Activity .
Feed shows you a summary of everything that's happened in the channels you follow.
Click Filter to show only certain types of notifications such as @mentions or reactions.
Select Feed > My Activity to see a list of everything you've been up to lately in Teams.