The Announcements page displays all announcements in a course and lets students filter them as needed. To open an announcement, click the title. New announcements may also appear in your Canvas notifications, such as email or app alerts, as well as in Recent Activity and the To Do list

Also see the instructions for Inbox: Some teachers use Inbox to communicate with students instead of, or alongside, Announcements. There, students can also send messages to other users in the course.