How can I see all my iCloud backups

"all", What exactly do you mean by that word "all"?

iTunes/iCloud backup stores only what you have on your device.

Each time you take a backup the data is either Added / Deleted based on what is available on your device. In other words, you only have one backup at any given time for a device. Though iCloud archives previous week's backup.

So you only have 2 backups for iCloud

However, in iTunes, you may archive an old backup and create a fresh one. --> Create Multiple backups on iTunes for the same iOS / iPad devices

As SravanKrA stated, iCloud saves two backups for each iOS device. The only way that you can see both of them is to erase the device and set it up again. When you get to the part where you can select a backup to restore, you should see both backups there.

See this in order to illustrate what I am saying.

Restoring of a DELETED iCloud backup of a… - Apple Community