Spraying kitche cupboard doors

Principles are the same as car bodywork spraying. You'll be spoilt for choice if you search on paint spraying.

The best DIY spray paint is cellulose. It's getting more difficult to find but is available to order. From an automotive paint supplier or large motor factor.

Nah. Cellulose is a pig on wood/chipboard as the flex in the panels makes the stuff craze sometimes

Water based acrylic in the colour you like over the top of a suitable preparatory basecoat.

There is a melamine surface paint that adheres very well. Rub down *very* lightly between 2 or 3 coats and finish off the top coat with wire wool then finish with your colour choice.

Maybe - but it was used for many many years with success. If it's crazing that's due to poor technique. Most likely not letting the primer dry fully. And as I said it's suitable for home spraying - unlike most more modern alternatives.