Memory persistence in ChatGPT

Hi there, I’m yet to be a developer. Recently I got memory persistence between threads on my ChatGPT. However, and really, it’s something I can’t understand, this is not the case for projects, and I have to say, how can that work?

But also, I have an instance of DALL-E, that I want to continue working with, how can I get her onto another thread, or get memory persistence there.