get a good dog, great protection and will hunt food.
start a collection of seeds and rotate with new ones every year, they only last so long (depending on specie). cereal grains are called such because they can be stored for long periods of time.
learn where you can procure salt. salt is more valuable than gold and is a must to preserve meat.
speaking of meat, keep it "on the hoof" until needed, salt and smoke are great preservatives
The best survival food depends on your area, and whether you're getting it from the store or out in the wild.
If you're getting it from the store I'd go with jerky, if you're getting it out in the wild I'd go with some sort of easily attainable meat like fish, or squirrel meat.
There is also the edible plants of the area, there's a lot to learn about that though, whereas with meat you can pretty much eat any kinda meat without having to worry about it. With plants it's a careful thing where you need to really learn the details of identification, one screw-up can land you in a hospital or worse.
As far as military tactics goes, all I can contribute to that is use your environment to construct a camoflage and hide in the woods, also travel in packs if possible, if not then you'll probably want to hide out and camoflage really well.
Shelter building is something to think about too, it depends on your environment largely when it comes to what sort of shelter to make, you'll undoubtably have trees present, and sticks, but what you'll want to know is what to use for rope so you can tie things together, there's a million ways to acquire some sort of rope or rope alternative. You can make rope from dead grasses by twisting them together, which there's good videos on that, definitely worth learning but if you need something quick you'll want to either go for a vine of some sort, or if you have the right kind of trees around the area you can strip them of their bark and make everything from rope to fishing line to fabrics.