I would suggest you use a csv file containing the desired info + the unique ID in separate columns.
You could then ask the user to enter the ID and preload the form with the information from the csv (if available). The command would be 'pulldata()'. Depending on whether the info come in separate column or in a single one, you might want to have separate calculate fields to retrieve the data and then display them as needed.
Just to add on what Andrea posted, you need to prepare a separate file (csv), which contains all participants with their information. Then after use a pull function to fetch these details. Then after you can use a note type question to display them.
Check out this link, it can guide you on how to go about solving this
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