Hi, so me and my brother plan to winter summit Mt. Marcy from Adirondack Loj and I need some tips for the trip. So I think we are doing something not so ambition but because we aren't very experienced we could start here. I just need to know some details, like is it required to bring snowshoes, can we make a fire, what do we do about the water situation (do we fill up on the trail, how do we purify it?), and how long does it take to reach the dam and then summit from the dam because we will overnight it. What is a good turn around time and stuff like that. I think I cover everything but if you have any tips don't be afraid to write them. Thanks!
I recommend you read both of those thoroughly - they'll answer your questions about snowshoes and fires, as well as others you didn't think to ask.
As for water: depending on weather, you will often be able to find liquid water in a flowing stream. If not, you should have plenty of snow around for melting. Purification in winter is usually overkill, but the best treatment is simply to boil it for a couple of minutes. (Most other treatment methods work very poorly or not at all at low temperatures.) Note that water left in ordinary bottles will freeze solid in a few hours, so bring a Thermos.
"How long does it take" - how fast do you walk? Serious question, I can't answer that for you. Step one, get yourself a good trail map. Then read the distances along the trails you plan to take. For planning purposes, start by assuming an average pace of 1 mph. You may go faster if the conditions are good and you're in good shape, but you don't want to assume that without evidence.
"what's a good turn around time" - depends on your pace, again. Also, whether you dislike walking in the dark more than you dislike turning around, and how confident you are of finding your way back in the dark. In winter, the days are short, so if you're not speedy you may have to choose between walking in the pre-dawn and walking after sunset. Pre-dawn is usually the safer option - if you make a wrong turn, it's a short wait for daylight. Either way, pack at least two headlamps per person.
"stuff like that" - you sound like a complete beginner (never gotten water on the trail in winter before) so it's hard for me to guess what you know and don't know. Like, do you know what kind of clothing to wear? Could you navigate in bad weather? Have you had any practice camping in the winter? Good ideas for what kinds of food won't freeze solid?
I'd suggest that Mt Marcy not be your first winter peak - it's a long, hard hike, and you'll be a long way from useful help if anything goes wrong. Camping at Marcy Dam is perfect for you - you'll be near enough to the ranger station to get help if you need it - but from there to Mt Marcy and back is a long day. Try something like Cascade first.
Note that Marcy rescues go back to the 1800's and are some of the nastiest. There's usually a bad one every couple years. The upper vertical 300' or so are above treeline and if one gets lost w/o map/compass (a real one not a phone) and the ability to use them, one cannot tell where they are. Dozens have ended up in the gorge between there and Haystack which is riddled with cliffs. There's still a body missing from a few decades ago. My point is to support the comments above. This shouldn't be the first winter peak. Cascade is an excellent one to start with. You can dial in your layers, water, gear etc. on a well-traveled trail fairly near the car. All the trails have been very icy lately (hard water ice) so familiarity with crampons is necessary (not micro spikes) and, of course, mandatory snow shoes w/ snow over 8". Good luck and be safe.