It is possible to obtain information about your penalty strokes by requesting a personal data export from Garmin. This can be done by visiting the following website: https://www.garmin.com/nb-NO/account/datamanagement/exportdata/
From there, navigate to folder DI_CONNECT, then to DI-GOLF, and finally to Golf-SCORECARD. By leveraging suitable Excel skills, you can gain an overview of all your penalty strokes.
However, it is worth noting that this method is unnecessarily complicated. Garmin should prioritize adding this feature directly to their user interface, allowing users to easily and efficiently retrieve this information without having to go through such cumbersome processes.