In order to delete a locked file, the process is pretty simple. If you want to delete one locked file, simply move it to the trash folder, and when you click "Empty Trash..." or press "Shift + Command (Apple) + delete," make sure you hold down the Option key. For multiple locked files, hold down Shift and Option while you empty the trash folder of your Mac computer.
Changing or moving locked files can be a burden, though. You can click on the file, choose "Get Info..." or press "Command + I," then uncheck the 'Locked' checkbox, but what if you have a bunch of files to unlock? Luckily, there are a few shortcuts that you can use to unlock these files:
1.The quickest method is to select all the files you want to unlock, then press "Option + Command + I" (or hold down Option while choosing "Get Info..." from the File menu) to open one Info pane for all of them. Then uncheck the 'Locked' checkbox, and you're done!
2.Another method, a little more involved, but possibly better for certain situations (like files spread through a variety of folders), is to open up the Terminal (in Applications > Utilities) and enter:
chflags -R nouchg <directory_name> (where the <directory_name> is the path to the parent folder.
3.A third method is to download a utility like LockMeBaby (from Soramimi Works) which performs the above steps for you.
After following the above steps, you will be able to delete your locked folder on Mac.