is there any way to read my imessages through icloud on a pc?

If what you're after is old messages and not new ones, back the iPhone up to the PC with the Apple Devices app (or iTunes on older Windows). Messages are inside that backup, and there are tools that can open a backup and export the messages to read or print. Turn encryption off for that or most of them can't read it.

Not through icloud, no. Messages in iCloud only syncs between Apple devices, the icloud website doesn't have a messages app at all. Closest thing on Windows is Phone Link, which can pair with an iPhone over bluetooth. You can send and receive imessages with it but it's basic: no group chats, no photos, and you only see messages that arrive while it's connected, not your old history.