This information is from :https://www.quebec-cite.com/en/plan-your-trip-quebec-city/how-to-dress-winter

Winter in Québec can be rugged and highly variable. It isn’t uncommon for temperatures to swing from -20o Celsius (-4o Fahrenheit) up to about 0o Celsius (32o Fahrenheit) in just a few days. Being prepared is the best way to appreciate all the magic of a trip to Québec between December and the end of March.

The Three-Layer Rule

Obviously, you’ll want to keep your body warm and dry at all times. That’s where the three-layer rule comes in.

First layer: The first layer, the one that’s in direct contact with your skin, needs to be warm and wick moisture away from your body. If you’re going to be active, a technical base layer from a sports shop is your best option. It’s also a good idea to bring an extra base layer so you have something dry to change into after working up a sweat. This effectively doubles your outdoor playtime.

Second layer: The second layer is meant to insulate your body. Fleece or softshell jackets are good options. Like your base layer, it’s best if your mid layer breathes, to allow moisture to move away from your body. Your mid layer is the one you’ll take off in warmer weather or for sports activities.

Third layer: Your third, or outer, layer is to protect you from wind, rain, and snow. Ideally, you’ll have different outer layers for different types of activities. To walk around town or attend an outdoor event, your outer layer should be as warm as possible. Down jackets and pants are one of the best ways to keep out the cold. For sports activities, your outer layer should be breathable. Thin, waterproof (Gore-Tex) clothes are generally your best bet.  

Accessories

• Tuques (beanies if you’re in the U.S.) are an essential part of any cold‑weather outfit. Covering your head is crucial if you want to stay warm. Plus, tuques protect your ears—one of the first parts of the body to get cold.
• A good pair of insulated gloves works fine for walking around town; waterproof mittens are best for playing in the snow.
• Wear long johns to protect your legs from the cold. If you’ll be spending an extended period of time outdoors, it’s a really good idea to wear snow pants. Don’t worry about being fashionable. Snow pants are standard apparel in Québec—even in the heart of the city!
• Your winter boots need to have good grip and be insulated, but mostly waterproof. Bonus points if they have a removable lining.
• A scarf or neck warmer will protect your neck from the cold and can be pulled up to cover your nose and mouth.

 A Few Tips

• Avoid wearing cotton. It’s hot in the summer, cold in the winter, and takes forever to dry.
• Keep alcohol consumption to a minimum. The “warming” effect is very temporary and your high spirits may keep you from feeling the cold.
• Bring an extra pair of socks and mittens to keep your extremities dry.
• You can also buy heated insoles that last for several hours or little pockets that release heat and slip easily into your mittens or boots.
• There are even heating clothes (jackets, pants, and boots) specially designed for motor sports that you can plug right into your snowmobile to stay warm on the trail.
• Some snowmobiling rental companies and dogsledding centres rent warm clothing.

For your flight: 

• Backpack 
• Valid passport 
• Flight itinerary  
• Copy of travel/medical insurance, including number and contact information  
• Debit Card 
• Credit card 
• Cash (CAD dollars) 
• Refillable water bottle 
• Medication, if applicable 
• Changing clothes in the backpack  
• Comfortable walking boots and hiking ones, winter coat, hat, sweaters 
• Small toiletry bag (Toothbrush/Toothpaste, deodorant, talcum powder etc) 

Luggage: 

• 1 big one to be left at Hotel while exploring 
• Luggage Tags and Locks 
• Backpack for adventures 

Clothing: 

• Comfortable clothes for traveling, exploring the rural areas and enjoying Québec 
• Long sleeves shirts and pants for trekking  
• T-shirts (synthetic or wool, quick drying) 
• Hiking Pants (Quick dry, Lightweight) 
• Waterproof/windproof Jacket & Pants 
• Gloves, mitts, hats, scarf 
• Snow pants 
• Thick leggings, long underwear 
• Sleepwear 
• Sweaters 
• Jacket 
• Bathing suit 
• Flip flops

Footwear: 

• Warm  boots – comfortable, casual for travel/town wear 
• Hiking boots – supportive, good tread, and waterproof 
• Hiking Socks (heavy socks) (Synthetic or Wool)

 Personal accessories: 

• Sport Sunglasses / Ski goggles 
• Sunscreen and Lip Balm (30 SPF) 
• Refillable water bottle  
• Travel Towel, quick drying/lightweight, optional 
• Hand sanitizer (bottle of 100 ml-3,4 floz or less) 
• Personal First Aid Kit/Medications (Lightweight) 
• Trekking Poles (recommended) 
• Electrical Plug Adapter and Converter if necessary  
• Camera and Accessories 
• Batteries charger
• Toiletries