My advice for anyone in a similar situation is to go for a job in a different field.
Tell them that you reached the goals you had set for yourself in your previous field (PhD, published peer reviewed works etc). Tell them that you feel it is time for you to explore other fields and that you have an affinity with the one you're applying in. Then tell them the most important thing you learned during your previous endeavors: you have the capacity to learn and adaptI'm following this dude from now on. Who knows when he burps out another wisdom nugget from his mouth.
Edit: I'm following this dude/gal/person/dragon/alien/chair from now on. Who knows when he/she/they/it burps out another wise nugget from his/her/their/its mouth.
Still learning to be all inclusive. It'll take me a while.
But you DO have a PhD. Claiming it is somehow not valid is a criticism of the establishment that awarded it to you. You're just suffering from impostor syndrome, that's all.
Also, no employer will consider someone fresh out of education, even someone with a PhD, to have vast quantitites of useful real-world experience, so even declaring a PhD won't see you land your first job with the expectations that you'll ace every bit of it from day one.
It's good that you realise you know nothing. That is both accurate and useful. But don't take it too far. What your PhD proves is that you have an ability to learn, understand and communicate, and THAT is what employers are looking for.