Ok I haev a dumb question about this but Ill use my numbers as an example

I need to take in 3187 calories a day
3687 to bulk
2687 to cut

I want to bulk so i would have to eat 3687 after addin the 500 but heres the thing the last year or so i take in maybe 2000 a day so wouldnt i want to to take in 2500 to bulk????? 1600 plus calories is a big jump.

Also off hand 3500 calories on a 40/40/20 split is 1400 calories of carbs
1400 calories of protein and 700 calories of fat now if i get my 700 calories of fat from eating chocalte or chicken parms and pizza????
Im sorry but im not quite understanding how this works

I want to do this right i did a cycle last year an wasnt happy wit the reults i dont want to do another one and i dont take any supplements so i want to get a very clear understadning how eating right.