How can I stop to be charged from whether app

Deleting the app does not cancel the subscription.

You need to go into your Settings app, tap on your name used with your Apple ID at the top, and head into "Subscriptions" to cancel the renewal.

See: https://support.apple.com/en-us/HT202039

Which weather app are you using? However your may --> View, change, or cancel your subscriptions – Apple Support

You may get better and prompt responses if you may kindly provide the iPhone Model that you have and the iOS version if it is known to you.