Getting your Firebase config (5 min, free)

1. Go to console.firebase.google.com
2. Click Add project → name it anything → continue
3. In the left sidebar: Project settings (gear icon)
4. Scroll to Your apps → click </> (Web)
5. Register the app → you'll see a firebaseConfig object
6. Copy apiKey, projectId, appId into the fields above
7. In the sidebar go to Firestore Database → Create database → choose Start in test mode

Test mode is fine for personal/family use. Your config is saved in the browser only.