"mix two chemicals and make a safe cooking fire, WITHOUT using wood or natural gas"
Not happening, unless you use some other flammable fuel to start the fire.
You have to have something to start your fire, and keep it cooking.
Get a copy (at a store or from a library) of the late Colin Fletcher's book **The Complete Walker.** Everything you need to know about fire starting, fire safety, and so forth.
The easiest camp stove to use is probably a white gas backpacking or Coleman car camping stove, which are what I use.