Bending back a bent head tube - is it worth trying?
I personally wouldn't ride this frame. The degree of localized distortion means the steel will be work-hardened at that point and will fatigue, crack and the front of the bike will collapse under you. I like my teeth where they are.

Yes, steel frames can be re-aligned if bent, but only if the deviation is spread out over the length of frame tubes, not concentrated in a small area.

Also, you will never get the head tube angle back to what it was, and will probably crush or ovalize the head tube in the process.

If you want to keep the frame, contact the builder talk to them about replacing the head tube and damaged sections of top and downtubes.