What if I back up to cloud it doesn’t change my storage

Again, backing up will not in any way reduce the local storage on your iPhone. Backing up does not delete anything on your iPhone as such there is no way for it to reduce storage use on the iPhone.

To reduce storage space, the only option is to delete content form the iPhone. Delete Apps, remove photos, transfer files of the iPhone etc.... Backing up either to iCloud or iTunes does not reduce storage space used on the iPhone.

Sometimes using iTunes may release some space used up by temp files or other things but it's not directly related to the backup.

What storage are you looking at exactly?

The iPhone local storage will not change because you backed up.

The iCloud Storage used may or may not change depending on what the backup did. If you recently backed up, and then backed up again it probably won't affect the storage space since there likely would be nothing new to add to the backup.

Its also possible even if things did change, they changed in such away as to not affect the storage space much. Somethings may have bene removed and replaced by other newer things that use up the same amount of space.