Explanation

Step 1: Import data into Common Data Service.
AI Builder requires the use of Common Data Service, which is the data platform for PowerApps and allows you to store and manage business data. Common Data Service is the platform on which Dynamics 365 apps are built so if you're a Dynamics 365 customer, your data is already in Common Data Service.
Step 2: Train the model
Step 3: Publish the model
The last step is to publish your model.
Step 4: Use the model in PowerApps or Microsoft Flow.
Reference:
https://docs.microsoft.com/en-us/ai-builder/build-model