How can I retrieve deleted text messages

Are you aware of the information in Keep your messages up to date with iCloud - Apple Support ?

iCloud Messages is a syncing service; you can only view iCloud Messages from one of your devices, not from www.icloud.com and if you delete a message from a device it is also deleted from iCloud Messages.

See the following Apple Support article for information on recovering deleted texts: Recover deleted text messages on your iPhone or iPad - Apple Support