A family of Microsoft word processing software products for creating web, email, and print documents.
1
If that is a Word file, open Word, select the File menu at the top of Word, on the resulting Recent list, are you able to find the location where that file may have been stored on your PC?
2
If you use OneDrive to sync your files to the cloud online, have you logged into OneDrive (https://onedrive.live.com/) in a web browser to check if the file is available to download from there.