The average adult needs 2000 calories a day.
Maybe you’ll need more if you’re taller, have a larger frame, or work out a lot (ex. if you run for an hour every day, you probably need closer to 2400-2500 calories per day).
It’s possible you’ll need slightly less if you’re smaller or shorter.
But you should never intentionally go for less than 2000 calories. When it comes to food and health, it’s almost always better to have too much of something than not enough.
If you are eating less than 2000 a day and it’s not been medically recommended for something like a serious digestive issue or recovering from something that made digestion difficult, please please PLEASE see a doctor.
And if your doctor tells you to eat less for reasons other than digestive issues, please do your research and consider if they have your best interest at heart. It’s one thing to tell you to cut something down (for example, you have a doctor who tells you to eat fewer sour foods because they’re destroying the lining of your mouth) and another to say ‘eat fewer calories than your body needs to help you function day to day’. The first is legit medical advice, the second is something you need to seriously reconsider listening to.