Step 1: Connect to your FileZilla using your FTP credentials.
Step 2: Locate the directory where the folder/file is uploaded.
Step 3: Right click on the folder/file that you wish to change the permission and select File permissions option.
Step 4: Enter the permission number in the Numeric Value field. Once done, click on OK button to save the changes.
Step 5: Changes done in FileZilla is automatically sychronized to your cPanel.