Even without being in a 'team', there is a lot of value to using the chat capabilities of Microsoft Teams to chat with friends and colleagues on campus. The "team" features enhance basic chat, to create a collaboration space where people can meet with their group, class, or organizational area to communicate and accomplish goals together
Microsoft Documentation
Microsoft has excellent documentation for creating a new team, however we recommend areas choose to create a "private" team when creating a team, and then adding members who comprise your team