yitzak wrote:
The door is in good condition, was new a few years back and so has
only had one coat of gloss on top of the undercoat. A few small
cracks have appeared. Want to paint it again.

Do I need to undercoat it? If so is it ok to undercoat with a white
undercoat and then paint it with black gloss? Or can I directly apply
another coat of gloss seing as its in good condition

Any recommendations of paint would be appreciated?

Rub it down with wet&dry to get a nice smooth finish and use a GOOD paint
brush with johnson's exterior gloss paint