How do I access my data stored in the iCloud?

It depends on what data you are looking to access. For example, if you were storing data like Contacts, Reminders, Notes, Photos, Mail, etc. then you look within those app on your iPhone like the respective Contacts, Reminders, Notes, Photos apps, etc.

There is nothing in iCloud that you don’t already have on your device or have access to through an app that works with iCloud. iCloud is a syncing service and not off device storage. If there is data in iCloud, it is already in your device or can be downloaded through the app in which iCloud stores the data.

Exactly what are you trying to access in iCloud that is not on your device?

iCloud.com - You can access some of the data here including photos, iCloud Mail and Contacts :)

Text messages - will be in the Messages app.

Photos - iCloud Photos.

Browser history - Check Safari.

Emails - Check Mail app.

You're welcome, good luck.

You are not going to find anything ever deleted. That’s not how it works, but you can have it. However, it will be futile. Just so you understand, iCloud is NOT off device storage.