How to access ICloud so I can manage it’s contents.

You will only be able to see specific things in iCloud, such as photos, calendar, etc. Go to www.icloud.com on a computer browser, and log in with the iCloud ID you are using on your devices. Make sure you have a device close by as you should be prompted to enter a code on the computer, and that will be sent to your iPhone. From there, you will see the icons of the content you can view.

One thing you cannot see are the contents of any iCloud backups.