Even if you find a key, the activation servers may not always honor it for new installations, especially if the license was not previously registered to your hardware. Recommended Alternatives
Community members and experts generally advise against trying to find old trial keys due to security and activation hurdles.
Microsoft ceased distributing trial versions of Office 2010 shortly after the release of Office 2013 and Office 365. Critical Review of Online "Free Keys"
Since Office 2010 is obsolete and potentially unsafe, consider these modern options:
You can use basic versions of Word, Excel, and PowerPoint for free in a web browser via Office.com.
Microsoft offers a one-month free trial for its current subscription service, which includes the latest versions of Word, Excel, and PowerPoint.