how can i view my icloud backup from my laptop

You cannot view the contents of an iCloud Backup from any device. You can only use the backup to restore or setup a device.

You can view synced data (e.g., iCloud Photos) by using an internet browser and logging into www.icloud.com

Also you can do the following (from Manage your iCloud storage - Apple Support ):

(I believe this will also display the date and size of the backup)

Windows PC

1. Open iCloud for Windows.
2. Click Storage.
3. Select Backup from the items listed.
4. Select one of the device backups, then click Delete. If you want to turn off Backup and remove all backups for that device from iCloud, choose Delete when you're asked to confirm. 

When you delete a backup, it also turns off iCloud Backup for your device. You can turn iCloud Backup back on in iCloud settings on your device.