You will
never know the exact
calories, so you just need to do your best to
estimate (e.g. learn what 3oz chicken or 1 cup rice looks like so you can use that as a standardized value and make
estimates based off that).
I will assess your previous
calorie / macro intake (if you have
never tracked that I'll have you eat «normally» for a few days while tracking to get this
estimate) and recommend «baseline macros» for you to adhere to.