How do I lose belly fat?

Iam a 13 year old female. Iam 5’6 and 130 lbs. I want to lose 2 pounds every week. How can i do this? How long should i work out on the treadmill and how many mph?

AND

If i have a daily intake of 1400 calories, and i lose 1000 calories a day, will i lose any weight?