diet help

[rsx4sh0]

im 20 y/o 163wt 5'8ht and trying to gain lean muscle...i train 5 days a week and need to work on doing more cardio. i would like to get a 6 pack but i dont want to loose my size of my arms n chest back ect is there a way to do it w/o loosing that? ive been working out for about 3 years and i stopped for about 3 months and want to get more serious and diet better.

my diet consists of
meal#1 chicken breast around 11 what would be a good morning breakfast other then eggs?
meal#2tuna sandwhich or pb n j sandwhich
meal#3 protein drink
meal#4 chicken or beef change it up somtimes
meal#5 varies steak..steamed chicken..chicken parm..
i see everyone posting diets do they change them up ever or stay with that 7 days a week??
tell me where to fix and or if it seems ok all input welcome thanks