Hi @Dawn Anglicas
Microsoft Teams doesn’t have a built-in feature to show when a file was last opened directly in the Files section.
To get this feature more quickly, you can send a feedback directly to Microsoft Feedback to add it in future updates.
Many features of our current products are designed and upgraded based on customers’ feedback. With requirements like this increase, the problem may well be released in the future.
As a workaround, you can edit the file every time you open it, so you can sort the files by Modified (edited time).
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