I don't know if you guys eat beef or not, but it looks like you have alot of things you could make with it, like tacos, spaghetti, etc. Tuna for casserole (with egg noodles, canned onions, and celery soup.) The muffin mix could be a fun breakfast treat one day, or for snacks in lunches. Nachos with the cheese dip and chips, olives, salsa. Popcorn for snacks, obviously. Same as animal crackers.
You could do some an and filling easy soup with some bacon or sausage, fried with onions and celery and/or carrots. Then add chopped potatoes, water, and milk. Simmer until the potatoes are cooked. Mash them into the soup, add salt and pepper, garlic, etc. Or you could use the chicken breasts, the broth you already have, and throw in whatever vegetables you want, some rice or noodles to make it a little more thick and filling. Have with the crackers.
You can have eggs and pancakes for dinner one night. With some kind of fresh fruit and juice or milk. Pizza one night with cut-up veges or salad. Oatmeal in meatloaf instead of breadcrumbs is really good.
I would probably buy in-season fresh vegetables and good-priced fruits, milk, eggs, tuna, ground beef, celery, cheese if you wanted to make tacos or something. I'm running around here, not thinking that clearly,

but you could easily make a meal plan and then go through the grocery store sales and see what else you could get for cheap to build meals around.
Good Luck, and welcome!
Kerri