This application using docker, docker-compose to run. So I suppose that you can install these two things.

• ./session/my_telegram.session.sesion: This is a database for pyrogram - a telegram client lib
• ./config.env: Environment variable for this forwarder

TG_API_ID=xxxxxxx
TG_API_HASH=xxxxxxx
TG_SESSION=/telegram_forwarder/session/my_telegram.session
FORWARD_CHAT_IDS="chat_id_1:chat_id_2"
TARGET_CHAT_ID="target_chat_id_1:target_chat_id_2"

TG_API_ID and TG_API_HASH: Telegram api id and hash of your application. Reference: https://core.telegram.org/api/obtaining_api_id

FORWARD_CHAT_IDS: chat ids of channel/group/user you want to forward message from

TARGET_CHAT_ID: chat ids of channel/group/user you want to forward message to

• Build docker images: docker-compose build
• Start the app: docker-compose up -d