Thanks for reaching out to us. I think you are referring to Form Recognizer Custom Model function.
You can add your receipts (at least 5) to do the custom training, you need to label what you want to extract so that the model can read it next time.
By using custom models, you can analyze and extract data from forms and documents specific to your business. Custom models are trained for your distinct data and use cases. A custom model is a machine-learning program trained to recognize form fields within your distinct content and extract key-value pairs and table data. You only need five examples of the same form type to get started and your custom model can be trained with or without labeled datasets.
You can either do by Studio or Labelling tool.
A quick guidance is here: https://learn.microsoft.com/en-us/azure/applied-ai-services/form-recognizer/quickstarts/try-v3-form-recognizer-studio#getting-started
Hope this helps!
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