It depends on the type of chat system your workplace is using. If you are using an internal messaging system, then it is likely that your boss has access to view any conversations taking place on the platform. However, if you are using a third-party service such as Slack or Microsoft Teams, there may be some settings that can limit their visibility into those conversations. It's best to check with your IT department for more information about what level of visibility your boss has over these communication channels.