The simplest and most common way of managing access rights to photos is to use album permissions.
To find out how album permissions work, read the dedicated article in our online documentation: Permissions and album visibility.
If you're not happy with permissions per album, you can also manage permissions per photo using confidentiality levels. You can manage permissions by photo and by album at the same time, without conflict.
To find out how to set and use photo confidentiality levels, see the dedicated article in our online documentation: Privacy levels.