If you can’t move or copy a file or folder on Mac
If you can’t move or copy an item, you might need to change its permissions settings. You might also need to change permissions settings for the disk, server, or folder where you want to move the item.
On your Mac, select the item, then choose File > Get Info, or press Command-I.
Click the disclosure triangle next to Sharing & Permissions to expand the section.
Click the pop-up menu next to your user name to see the permissions settings.
If you’re not logged in as an administrator, you may need to click the lock icon and enter an administrator name and password.
Change the permissions to either Read & Write or “Read only.”
If you need to, also change the permissions for the location where you want to put the item.
If you can’t change the permissions, contact an administrator of your Mac or the owner of the file or folder.