Possibly melting snow is the most critical skill of winter camping. You can be cold, wet, etc etc and get by, though uncomfortably, but without warm (unscorched drinkable) water you will not last long in the cold. Eating snow takes a huge tole on you core warmth and should not be done. In the worst case, I hate to say this, but a zip lock with snow in it under your coat can at least melt a bit before you drink it. ice cold water has a lot more heat in it than snow at the same temp.

If you have a pan and a fire but no melted water and lots of snow, you still need the skill to get warm water. Hold the pan like 6 inches above the heat for 30 seconds or so - only enough to warm the pan, not scorch it. Then put in 1/2 teaspoon of snow (NO MORE!!!!!) and swirl it around in the pan till it melts and repeat the process 2 or 3 times. Now you can heat that little bit of water till its hot (maybe) and then add an amount of snow that when melted will no more than double the total amount of water. (adding too much snow it will absorb the water and scorch)Do this a couple of times and you will have half a cup of warm water. Now you can heat it to near boiling and then put in more snow.

You must stir constantly, and if your heat is a summer canister stove, dunk the fuel bottle in your warm water (NOT HOT) to warm the fuel canister and keep the stove going.

I've seen a frozen 5 gallon bucket of water put on a campfire and most of it steamed away (scorching the bucket and ice) without yielded melted water. Water goes directly from ice to steam if there is too much energy. You must gently warm ice or snow to get a liquid state. Had we warmed the bucket gently at first, we would have had a bucket full of hot water that could be drunk.
Jim