Go to Settings > Advanced > Export Telegram Data
From there you can choose what you want to export:
Account info, Contacts list, chat info, media...
You can also try this to export the contacts.
https://github.com/salarcode/ExportTelegramContactsIt was suggested here:
https://android.stackexchange.com/questions/146157/how-do-i-export-telegram-contacts-to-my-phoneYou can also try with a software called
http://telegramauto.com/ Here is a video explaining the process
https://www.youtube.com/watch?v=yj9XmfwQ4fgI scanned the URL and it seems clean
https://www.virustotal.com/#/url/4fd23a6b8635425082ddc93170af845d2aad14f1071056f7b52a64c6c9624e38/detectionStill, I haven't used the software I suggested so use it at your own risk and make sure you scan all of it.
Also, this thread is not Bitcoin related so you should move it to the Help & Beginners section.