Telegram recently launched a screen sharing feature for its users, and screen sharing allows participants in a group video call to share their mobile screen and view documents, videos, or anything they want others to see.
Here's how to use this new feature
Open the Telegram app on your phone.
Open a group chat in which all members are present.
Click on the group icon.
Click the chat box icon with waves in the middle at the top right to start a voice call with that person, (you can also turn on your camera and make it a video call).
Click on the three vertical dots in the voice chat bar and select Share screen.
Grant the screen share/cast permission to the app.
Now the participants of the call will be able to see your screen on which you can show them the content you want to share.