There isn't a one size fits all as your daily energy needs are determined by a lot of different factors.
This link will take you to the energy needs calculator.
http://www.weightloss.com.au/weight-los ... ulator.htm
To lose weight you need to have a calorie/kilojoule deficit. So you need to burn more than you consume. To do that you can either have less calories/kilojoules from food, burn more through exercise or a combination of both.
As an example I have a food calorie deficit of approx 30%, so I consume 30% less calories than my body needs. I then get a further deficit with the exercise that I do.
Hope that helps.