There are three different ways to use Google Chat on a desktop computer:
Gmail: Open your Gmail account in a web browser. In the left column under Inbox, you’ll see a preview for Google Chat direct messages and chat rooms. To open the Chat app in a separate window, click the grid icon for all Google apps in the upper right corner. Scroll down in the menu and find the icon for Google Chat. Click the icon and Google Chat will open in a new tab or window in your browser.
Web browser: In the Chrome browser, Google Chat also automatically appears in the Google apps menu when you click the grid icon in the upper right corner. Alternatively, you can open the app in any browser by entering the Google Chat URL.
Progressive web application (PWA): Another option is to use Google Chat as a PWA on your computer. To do this, open the Chrome browser and log into your Google account. Now click the three-dots icon at the top right and select Install Google Chat....