To make your bot works firstly you need to creat bot via @BotFather in telegram. After you get a token you should write it down to your json5 config(create file config/default.json5). Telegram API is blocked in some countries, so you may need to use proxy. To get weather forecast you also need to get apiKey. Config file should look like:

{
   token: '12345:ABCDEFG',//telegram token
   proxy: {
     host: '100.100.100.00',
     port: 3000
   },
   apiKey: '1314asd12312qwe' //openWeatherMap
 }

npm install

then

npm start

Enjoy :)