First of all you need a firebase realtime database. Create new a firebase project for free: https://console.firebase.google.com/
Then you need a database token. Open your firebase project settings and create new database secret/token (see service accounts > Database secrets).
Install flow package:
composer require neoslive/hybridsearch-neos-demo
Add to your flow Settings.yaml
Neoslive:
Hybridsearch:
Firebase:
endpoint: 'https://** your firebase project name**.firebaseio.com/'
token: '** your firebase token **'
Run flow command for initial indexing your Neos.Demo Site
php ./flow hybridsearch:createfullindex