Setup

1. Obtain client_id & client_secret from console.developers.google.com
2. Goto developers.google.com/oauthplayground
   1. choose the Drive v3 scope
   2. click settings, select Use your own OAuth credentials
   3. Enter client_id & client_secret
   4. Click authorize apis and complete the process
   5. Obtain the refresh_token
3. Update system then install ffmpeg & all the dependencies

sudo apt update
sudo apt install ffmpeg
npm install @discordjs/collection ytdl-core youtube-sr googleapis fluent-ffmpeg

4. Fill in everything in playlist-download.js