What do l need to wear?

You can wear what you want. However, the reason for ski coats is, they are wind proof and water resistant.

well it really depends. If the weather is cold windy and wet then your going to want a coat that will protect you for that. if its sunny and warm you want a coat that will help with that. so no you dont need a coat that is a ski coat you need something that will keep you warm and dry on the hill

If it keeps you warm and dry.

Depends on the weather and your ability level. If its nasty outside, or if you tend to fall a lot, then you will want to have a coat with a high level of water resistance and that is wind proof. But on days where its nice outside, l usually just wear a fleece and maybe a light windbreaker over that.

Just use your head and you will be fine. No jean jackets in a blizzard, eh?