Integrated with OpenAI API and DeepL API, support audio and video messages, used library Whisper AI for speech-to-text recognition, integrated DeepL translate to convert messages to other languages.
You can try bot by following this link: https://t.me/Custom_gpt_bot
If for some reason you want to try run it by yourself or develop it any futher, you will need OpenAI API, DeepL API, and your own Telegram bot API.
Do not forget to put them into corresponding classes. OpenAI for Service class, DeepL for Translator class, Telegram bot for Bot class.
Also, for better understanding, make sure to check libriries used: https://github.com/rubenlagus/TelegramBots and https://github.com/DeepLcom/deepl-java.