Can't uncheck Read Only in Folder and files

I've done a lot of google searches with no fix.
I have a Folder on a USB external 4T drive that was originally on a different computer that I still have. It is a folder with many subfolders and 4500 files. The files were encrypted and I got rid of that, but are all Read Only under Properties
I'm logged into Windows 11 with an administrator account to access and modify file permissions.
I have tried the regular things like:

Take Ownership of the Folder
Add Your User Account to the Security List
Grant Permissions: In the Permissions window, select your user account and then check the boxes for the appropriate permissions - ALL THE CHECK BOXES UNDER FULL ARE GRAYED OUT
REGEDIT
HKEY_LOCAL_MACHINE\\SYSTEM\\CurrentControlSet\\Control\\FileSystem.NtfsDisableEncryption: is set to 0