What do you mean, how can a telegram group steal your bitcoins? Did you send them to someone claiming to be an admin or offering investment opportunities?
Some more info would be appreciated.
The Icenter is a robot, that you download using the telegram, https: //t.me/icenter_bot.
He does trading for you, promises interest of 1.2% for day! You deposit a minimum of 0.01 BTC and gradually it will investing etc.
The problem is you can not take your money any more!