The stove is your main tool. Decide how much money you're willing to spend. Find a stove with at least two burners. You'll often want to be heating or cooking two things at once. See what kind of fuel the stove uses.
White gas is the most widely available and is quite cheap.
It also burns relatively cleanly. Propane is another popular option, but often requires discarding empty canisters creating unnecessary waste. Make sure the stove will work at high altitudes, so you don't end up eating raw macaroni. Check what form the fuel supply comes in. If possible, buy a stove with a reusable fuel tank or canister.