Recursive Permsisions on EXT HDD?

I have an ext hdd with my photo library on it.

I was having permission issues with that drive and attempted to:

get info

unlock

add ➕ admin with read and write permissions

apply to enclosed folder

lock

No errors, admin is added to the list of users, but there are folders on the drive that do not show the change I made to the permissions, so they are not behaving the same way in my photo application (Lightroom)

Its about a hundred folders, I could select each one individually and change the permissions, but that would a bit arduous and if I select them all and get info I have a hundred get info boxes on my desktop?

Wondering why these folders refuse to have there permissions changed and what is the best thing to do about it?

Thanks,

Henry