how to read messages in icloud

Messages can be synced through iCloud but there is no option to access them using an internet browser at iCloud.com. Also see the following from Use Messages in iCloud - Apple Support

You can use Messages in iCloud on your iPhone, iPad, iPod touch, Apple Watch, and Mac. For your privacy, Messages in iCloud is end-to-end encrypted,* which means you can't view or access Messages online via browser. 

If you had iCloud Messages ( Use Messages in iCloud - Apple Support ) turned on then your messages are synced with iCloud (and your other devices if it was also turned on in them) and they are not included in an iCloud Backup. Syncing includes all changes made to messages, including deletions -- if you delete from a device they are also deleted from iCloud. See the following from What does iCloud back up? - Apple Support

When you use Messages in iCloud or turn on iCloud Photos, your content is automatically stored in iCloud. That means that they're not included in your iCloud Backup.

If you did not have Messages in the Cloud turned on, then messages would be included in an iCloud Backup. You cannot view contents of iCloud Backup; you can only use it to do a full restore (not just messages) of your iPhone or iPad which will replace all data that is currently on your device with the data from the time of the backup. See: Restore your iPhone, iPad, or iPod touch from a backup - Apple Support

demetra258 wrote:

I guess I didn’t get enough clarity… I need to access my messages on iCloud because I am looking for archive messages and messages that I have deleted on my phone.

You cannot go to icloud.com and view messages. That is not an option.

If you were using iCloud Syncing for Messages and you deleted them, they are gone. Full stop.

As noted in my previous reply, you view them in the Message app on your iPhone, iPad, iPod touch, Apple Watch, and Mac.