how to get permission to change permissions

Changing Permissions for files, folders, or disks is explained in Change permissions for files, folders, or disks on Mac - Apple Support, but yes more information would help.

You have to click the "lock" icon and authenticate with Admin credentials.

And if the file/folder is on the read-only system volume, you cannot get permission.

Do telling us what file/folder (full path please), you want to change the permissions on would go a long way in us helping you.

mylinguist wrote:

When I try to change permissions on my MacMini with M-4 chip and Tahoe, I get the message that I do not have permission to change permissions. I'm stumped. Any suggestions?

what permissions where exactly...?

what are you trying to accomplish, details would help...

If you are indeed trying to change permissions on a place you cannot, what is the problem that makes you think changing permissions will solve it?