The Rating input block allows you to ask your user for a rating.
Rating input in flow
The rating input is very customizable, you can set a custom range, numbers or a custom icon, and bottom labels.

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NPS

You could for example configure it so that it collects the Net promoter score:
NPS configuration

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Custom icon

To insert a custom icon, you’ll need to insert SVG content. It should start with <svg> and end with </svg>. You can find great open-source icons on Feather