Winsor & NewtonCotman Water Colours - 1/2 Pans, Field Box

As someone with no watercolour experience - What else do I need to buy apart from this to get started?

Do they dry quite chalky or nice and smooth? I like to work over what I paint with pens etc and chalky watercolours destroy my pens.

Im really confused. The picture shows this is the fueld set with the water bottle, but later it shows a different set. Which is it as there is a big

Can the paints be replaced in the plastic case once they've run out?