How can I look at my iMessages online on icloud

Hi, and welcome to the Apple (user-to-user) Community !

Re: "How can I look at my iMessages online on icloud:

"How can I look at my iMessages online and not using my device."

Am no expert in this area, yet your question surely deserves a response:

Seems iCloud is mainly for sync of data across all your devices.

Generally you would use one of your own devices for access to synced Messages online.

If you don’t see the apps or data you’re looking for in iCloud on a computer or device that is not your own:

For Tips: Scroll through the article below to:

"If you don’t see the apps or data you’re looking for"

How to: Sign in and use iCloud.com - Apple Support

More info. on Messages / iCloud:

Set up iCloud for Messages on all your devices - Apple Support

and

Keep your messages up to date with iCloud - Apple Support

For more info / support / contact:

iCloud support website:

iCloud - Official Apple Support

All the best :-)

You cannot. Messages are end-to-end encrypted and can only be viewed on your devices.