Question 1.
1kg = 2.2lb = 9.80665002864 Newtons
To calculate your mass in KG, you must divide your weight in lbs by 2.2.
To calculate your mass in Newtons you would take your weight in Kg, and multiply by 9.80665002864.
Question 2.
Mass is a measurement of the amount of matter something contains.
Weight is the measurement of the pull of gravity upon an object.
So mass does not change when an object's location changes, but weight can.
If you were lucky enough to go to the moon, where gravity is less than it is on Earth, then your mass would remain the same but your weight would be less.