Have a great trip!
I would second the buy as you go suggestion. You will have to do that later if you do longer tours and it will be good practice doing it now.
If you really want or need to carry everything... Boxed rice, noodle, or potato dishes are easy to pack and cook. Supplement with foil packed tuna or salmon.
If you buy near meal time... Almost anything you'd eat at home works for dinner. I kind of like to get frozen bag meals sometimes rather than actually cooking. Also bag salads are a good addition. A small bottle of wine is a nice plus.
For lunch bagels and peanut butter with honey or jelly are good. Wraps with foil packed tuna and some kind of durable veggies are good. Chips with hard salami and hard cheese and maybe an avocado can make a good lunch.
Snacks... Jerky, fig newtons, gorp, or baked goods in a jersey pocket or handlebar bag can be munched while riding or at stops.
Breakfast... My usual is to have a granola bar in camp or if I feel slightly more ambitious instant oatmeal. I am likely to stop later at a diner for second breakfast.
BTW, I find it much easier to shop and cook when traveling with someone than when alone. When alone I am much more likely to be lazy and either have a PBJ for dinner or stop at a restaurant.