Another way:

If you know how to mql4 coding, you can go to this topic to see the answer https://www.mql5.com/en/forum/285054/page2 and https://www.mql5.com/en/articles/2355

Otherwise, there are some utilities out there in mql5 website could help send the chart screenshot and message to Telegram, such as: https://www.mql5.com/en/market/product/32269

Good luck!