Would love some help with calorie deficits and 'cutting'

Hey guys! So I would love some help because I am confused! I have a Fitbit (yup I know some people don't like them haha) anyways I'm using mine for a rough guide for my calorie burn when I workout and for my steps, lately I've been noticing when I track my food it will give me a number of calories left over, so on my Fitbit it says I burn around 2700-3000 a day (this is what my body burns on it's own and a workout added together) . I eat normally at 1800-2000 a day, so it always says I have calories left. I've been reading online about calorie deficits and seeing on my Instagram of female body builders 'cutting'. Basically I'm wondering am I in a calorie deficit? Or am I eating normal amount? And to change up my weight loss do I need to drop some calories for a while to get into one? Also does 'cutting' mean the same thing? Haha I do need to drop the last 5 kilos and I've been at the same weight for two months now so I need a kick! Thanks guys