It also depends on what type of cardio you're doing... If you typically do low-moderate intensity at a constant pace, you'll want to aim for 250-300 mins per week. If you're able to do higher intensity workouts (interval training, HIIT, etc.) you're workouts tend to be shorter - max 30 mins each - but you don't want to do high-intensity everyday. So it ends up being a combination of low-moderate intensity workouts most days and high intensity 1-3 days per week.
"Proper" diet has a different meaning for everyone, depending on your goals. Some basic rules that everyone who is trying to lose weight can follow are things like:
1. MODEST calorie restriction (not extreme restriction as many people tend to do)
2. Avoid processed foods as much as possible (refined flour, sugary foods, salty foods)
3. Eat lean protein sources more often (turkey, chicken, fish, egg whites, low fat dairy products)
4. Eat 'fatty' sources of protein less often (red meat, pork, whole eggs, regular fat dairy products)
5. Eat more veggies and more fruit
6. Don't drink your calories - drink only water (no sodas! not even diet!), limit caffeine, and limit alcohol (alcohol alone has almost as many calories per gram as fat)
7. Eat breakfast!
8. Try to eat at least 3 meals a day, spaced at somewhat regular intervals. Some people prefer to eat 5-6 smaller meals throughout the day.
One thing to keep in mind is that not all of your protein needs to come from animal sources - meat, eggs, and dairy. I encourage people to get some of their protein each day from plant sources which do not contain cholesterol and tend to be much lower in the 'bad' fats. Plant sources of protein has the added benefit of having fiber, which helps to keep you full for longer and clear out the digestive system, keeping it healthy. Some examples would be beans, nuts, seeds, and whole grains, but many fruits and veggies also contain some protein.
Something that the dieticians that I've worked with recommend is the food plate method, which I find is a much easier method that calorie counting:
USDA Food Pyramid is Out, Food Plate is In
Hope this helps a bit!
Hope that helps a bit!