how do i get my deleted account back?

Here's a more optimistic reply ;-) Depending upon how long ago your requested deletion it may still be possible to cancel it.

From: How to delete your Apple ID account - Apple Support

"What happens if I change my mind after I have requested that my account be deleted?

While your request is being processed, you can contact Apple Support [using this link --> Contact Apple for support and service - Apple Support ] with the unique alphanumeric access code you received, and we’ll help you cancel your request. After your account is deleted, Apple can't cancel the request, reopen your account, or restore your data."

If you have deleted your Apple ID, then it is no longer valid, it simply no longer exists and it no longer works.

To understand about a deleted Apple ID, see the Apple articles below:

How to delete your Apple ID account

How to delete your Apple ID account – Apple Support (UK)

-> Once your account has been deleted, Apple can't reopen or reactivate your account or restore your data.

Understand and control the personal information that you store with Apple

Understand and control the personal information that you store with Apple - Apple Support

Get support from Apple directly -> Get Support or call Apple in your region see -> Contact Apple for support and service