[Quiet Man Cometh]

For starters, learn to cook at least basic things. Vegetables and raw food is much cheaper than prepared and instant stuff. That's one of the first things I learned in college. Also, if you have the option, shop around and look for the good prices on things. I've often found that fruit and vegetables from a farm market or veggie store are cheaper than those from a standard everything food market. Butchers are often cheaper for meat than an everything store, etc. Buy whatever is one sale.

Cooking actually doesn't require all that much. I hate doing it too but I managed well enough. Cooking veggies is easy because they can be eated raw anyway so there's no problems with undercooking on the health end.

Unfortunately, one of the only ways to deal with weight loss from not eating enough is to just make yourself eat more. The less you eat, the less your stomache is able to hold because it gets used to not having much in it. I've been there lots and it's not easy to do but making yourself eat more is pretty much the main thing to focus on. I had to have meal replacement supliments for a while when I was ill, and i still keep those around since I rarely eat breakfast. Those are pricey though.