Open Window > Save Game Pro > General Settings window:
Go to Install Integrations section:
Now, Click Install button next to the Firebase title to install Save Game Pro Firebase integration
Setup Database Rules
In Firebase you need to set up the Database rules in order to save and load data, we have a ready-to-use database rules that works the best in most situations:
".read": "auth != null",
".write": "auth != null"
For more information check out Firebase Get Started with Database Rules article.