I have an external hard drive with two Time Machine backups on it. One backup is being used for my current Mac and the other backup is from an older Mac that isn't used anymore.
I discovered that the permissions on some folders in the administrator account's home directory were wrong and files could be accessed from another standard account. I corrected this on the current Mac by running chmod 700 ~
when logged in as the administrator. This seems to have fixed the access issue, but the older time machine backups for both the current computer and the old computer still have the problem.
I would like to safely adjust the permissions for both backups so that none of the files are visible by the standard user. For the Time Machine backup that is currently being used, I am fine with only retaining the latest backups that do not have the permissions issue. I have not found clear explanations on how to do this in Ventura 13.2