Please try these steps;
Open File Explorer and check your Pictures folder, then look for a Scans folder.
Open the Brother iPrint&Scan or Brother ControlCenter software (if installed) and check the scan destination. It may be saving the file to a different folder.
Search your PC for recently created files:
Open File Explorer.
In the search box, type:
*.jpg
or
Sort the results by Date modified to find your latest scan.
If you're scanning from the printer's control panel, make sure it is set to Scan to File and that your computer is selected as the destination.