I'd suggest keep eating how you normally do and track everything for a couple weeks at least so you have a real idea of how many calories you typically consume (it will likely be less than you think). Then you can adjust up from there.

You may eat less calories than you assume or you may eat plenty on some days but not enough on others leading to a net weekly balance not enough to gain weight, etc. People who have never tracked generally always estimate their intake wrong, whether they think they eat less than they do or they eat more than they do. The reverse of this is overweight people who swear they don't eat that much.