WhatsApp will deactivate account. It happens permanently, as your account gets permanently deleted in 30 days, if you are not able to reactivate it in the 30 days.
Can I reactivate my WhatsApp account after deleting it?
WhatsApp allows you to delete your account permanently if you want. However WhatsApp lets you reactivate that account if you want to use it again on a different device.
Can I restore my WhatsApp account after deleting it?
Deleting an account does not delete the messages, but all the media will be removed from the app. If you sign in with the same phone number, your messages will be restored.
What happens when WhatsApp account is deleted?
In order to stop receiving updates, you are required to delete your account. If you are deleting your account you will not be able to regain access to it. Your information will be unavailable during this time period.