Once you have added Hangouts you’ll be able to join and create calls. Joining a video call from your Gmail is easy, and there are many ways you can do it.
Note: Sometimes people have trouble joining video calls because they’re signed in to a different account in their browsers. So make sure you’re signed in to the account your Hangouts invitations were sent to.
If someone starts a one-on-one Hangout with you, a chat window appears in the bottom corner of your Gmail screen (or, if you have the Hangouts Chrome Desktop app installed, in the bottom corner of your computer screen).
Click , and a new window opens with your Hangout.