It's sad how hard it is to find things that don't have preservatives or artificial flavours/colours etc or added salt/sugar. i simply dont have the time to make everything fresh from scratch, although i do my best. but really slim6y what you suggest isnt feasble these days!
Poowallops!
Fresh veges - ah huh... there's an entire supermarket section devoted to it...
Fresh nuts... Well.. crack a macadamia or a walnut... even peanuts (they're grown locally over the entire country)
Pulses like peas and beans you buy by the kilogram... you'd be crazy if you think these aren't available. Most don't need preparation.
Potato and kumara... taro and carrot....
Holy moly - there's so much I could run out of room....
Grains.. RICE... RiCe and glorious rIcE....
Fish, chicken, pork, beef, lamb, horse....
You can get most of these without hunting...
A little bit of cooking (same as usual) perhaps without oil if possible.... And you have an AWESOME dinner...
Rice with carrot and seared lamb....
Hell... my mouth is watering now...
Your lunch can be left overs...
Breakfast, fruits, and juice, served with eggs and beans....
I don't see it as being impossible at all.... In fact it's more feasible than the others....