If you are still planning to use Firebase as the database, you need to obtain the service account key (Project Settings > Service Accounts > Generate new private key) and put it in the project directory. Then, in the environment file, you need to put the path to the service account key in the FIREBASE_SERVICEACCOUNT_KEY_PATH environment variable.
You need to create a bot using BotFather and put the bot token in the TELEGRAM_APITOKEN environment variable.
Once the setup is done, you can start by installing Go from here (tested in version 1.20.4).
If it is installed, you can run install the required packages and build an executable file by running:
go install
go buildOnce it is done installing the dependencies, you can build the bot by running:
./james- Concurrency (especially on image processing)
Can be found here.