Trouble with adding & deleting photos

After many years of no problems with my pictures, having problems tonight.
Tried to delete a photo from my gallery. Clicked on photo options as usual. The choice for deleting the photo wasn't there.
Then tried to add a picture to my gallery and got the message that I don't have permission.
I'm not computer savvy, so my hope was that shutting my computer down and rebooting would somehow help. Well, it didn't.
Any suggestions ?

L & O

Trouble with adding & deleting photos