You have to reset your password first. It's either going to use your device (two factor) or security questions or rescue email (secondary authentication). If you can't use the secondary auth email reset you'll have to try to use security questions. If you don't know those contact support to help you. If it's two factor and you don't have access to a trusted device as outlined on the article I shared then you'll have to do account recovery. It seems to me your best option is to contact support and speak to an advisor to assist. Once you have full access to the account you'll be able to change it. If we can never get access to the account then you're not going to be able to change your Apple ID.
If necessary, there is a contact link.
Apple Support by e-mail or chat Select your device, Battery, Power and Charging, then Power adapter not working to get a chat option. If you need to talk to them, ask them if they will do a Skype or FaceTime with you.
Question: what to do when you have an apple id whith an unexisting email because i have deleted my email adresse