iCloud Photos vs iCloud Photo Library Backup

While creating a backup for the 1st time for my 3 years old iPhone, a backup with the name "Photo Library" is created. On researching, I got to know that this happens when your iCloud Photos backup is turned off, which actually was the case while taking the backup.

After reading several replies and suggestions on the Apple community, I have turned on my iCloud Photos and now when I go inside the settings or even in Photos, it shows the status as "Restoring". I have two questions on this:

1. After the backup is completed (which is already going on for the last few hours), what will be the right way to manage photos backup? - keep both the iCloud Photos and Photo Library or delete the Photo Library backup as both of them are redundant and will have the same information
2. What does restoring means in current situation?