Download Tor Browser for the platform which you are using for Telegram from https://www.torproject.org/ and launch it in the background. (App=just open orbot and connect)
Open Telegram. When the app asks for your phone number, instead go to “settings”
Click “Connection type”
Set it to “Use custom proxy”
Make sure “SOCKS5” is selected
For hostname, enter “127.0.0.1” and for port, enter “9150”
Leave “Username” and “Password” fields empty
Click “Save”
Make sure the screen says “127.0.0.1:9150 online”. This means you’re now connecting anonymously via Tor, using the Tor browser as a gateway.
Note that the Tor browser needs to be open every time you connect to Telegram. You can later double-check you’re anonymous by closing Tor Browser and seeing if Telegram displays the “Connecting…” or “Reconnect in x seconds” message.
(Also note that you can’t make previously existing Telegram account anonymous just by setting it to route via Tor, both register and use phase must be done anonymously using Tor routing and burners.)
Click “CLOSE”
Click “X” in the top right corner.