Create .env file and poopulate it with your Twilio Account SID & Auth Token. The .env file is included in .gitignore, so it won't be pushed to github
cp env.example .env
Homebrew is a global package manager. It allows you to easily install development packages into your global development environment.
ngrok is a tunneling package. It allows you to expose a local port to public URL. So, http://localhost:3000 becomes http://xxxxxxxxxxxx.ngrok.app