Real time price data you can see the price of any listed coin from Coin Marketcap. Apart from this it is also possible to see from the exchanger as you said. But why should you choose a telegram channel from wherever you track the price? Telegram is a scam empire so I don't trust anything from telegram. And I am not interested in doing anything with telegram and I can never imagine in terms of price tracking and trading signals
Well, it sounds like you've had some bad experiences with Telegram, so you no longer trust the services offered on this platform. Personally, I sent a link to a Telegram BTC price channel, and it's still working with pretty good accuracy, not significantly different from the BTC price on TradingView. I also know of many signal groups on Telegram, they're still doing well and attracting more members. I don't participate, but I don't object to their existence either.
Telegram is just a platform, we can leverage it to work more effectively in our own ways and according to our own criteria. I really like Telegram's features, even though I only use the free version. I use Telegram to store ideas, discuss things with colleagues, and it's also a data repository that I can access from multiple devices.