Google has already announced previously that Google meet will be integrated in Gmail in web and mobile as well.
Here’s the good news, Google has already launched this feature in the gmail web and now launched this in the mobile apps. It started with the iOS app and then rolled out in android app. After this users can join the video call from gmail app only without going to any other app.
Now, when you click on meet link anywhere, you will be redirected to gmail app for joining the meeting. But if you click meet link in meet app, you will be joining the call from meet app only. Google is working on this and users will get this update in coming weeks.
Also you can see all the functionality is same as you was seeing in the meet app.

Users can see the meet tab in the gmail tab as in the screenshot below. You can go to meet tab to see the scheduled meetings and join the meetings.

Users can choose to hide the meet tab in their g-mail tab. Users can go to gmail settings and UN-tick the option “Show the meet tab for video calling” under settings > Meet.

In the rolling out period, iOS users may experience a little different from android. At start when they click on the meet link, their g-mail app will be closed for a moment and user will be taken to meet app to join the meeting. After rollout, users will able to join the meeting in g-mail only.
This feature is by default launched to all users, Once you update your g-mail app, you will see the meet tab in your G-mail app.