You generally cannot view true Incognito/Private browsing history from the browser itself
Check DNS cache on the device
Check router or network logs if you have access
Check parental control or monitoring software logs
Check endpoint security or MDM logs on managed devices
Check browser sync activity on other signed-in devices
Check system-level activity logs on the device
Check downloaded files and recent documents
Check bookmarks, autofill, and saved passwords for clues
Use account activity logs for sites signed into during the session
If you do not own or administer the device or network, do not attempt to access private data