Have you tried reframing things for fun?

Lie to yourself for a bit, I suspect it's like muscle, the more you do it the better you get at it. That's kind of what positive affirmations are, you keep telling yourself certain things (within reason..) and it is supposed to steer your subconscious.

I kinda get where you're coming from. I had a similar problem. I found it difficult to "Fake it 'til you make it", but I did find it easier to abstract it one layer. It just made sense in my head to fake faking it until I could fake making it because that's just pretending to lie. It still just makes sense to me.

I struggle with this too. My therapist is trying to help me with some aspects of it, usually trying to use a past accomplishment and applying it to what I currently have massive anxiety about. Doesn't always work cause my brain treats that past accomplishment as a mistake or something I shouldn't have gotten.

I have a very hard time reframing things

Because you are not supposed to. Emotions exist one layer of abstraction lower than consciousness, hence frontal lobe can't override them manually. It's evolutionary safety measure

Could you create similar circunstances without the pressure? Say apply for jobs you dont care about so you are familiar with theprocess and experience of interviews.