For a visual guide on managing your storage and clearing out unwanted files directly within the app, check out this tutorial:
Since there is no recycle bin for messages, recovery is only possible if you have a backup: Trashbox Whatsapp Android
If your goal is to clear space, WhatsApp provides a built-in tool to review and permanently delete high-volume media: For a visual guide on managing your storage
If you delete a message, you can often recover it by uninstalling and reinstalling WhatsApp, then choosing to Restore from your most recent backup. Note that any messages sent after the backup was created will be lost. Third-Party "Trash Box" Apps Trashbox Whatsapp Android