You want a pure alcohol. Somoething around 99%. Most recommend heet (yellow bottle of gas line antifreeze), methyl alcohol (next to paint thinner), everclear (95%) or some variation on that.

How much you bring will depend on how much your stove uses and what type of cooking. Some need less than an ounce to boil 2-4 cups and some need more. Your best bet is to try out your stove at home and get an idea of home much you'd need for one meal and then multiply it by how many meals you need (include water boils if you don't filter) and then allow yourself a buffer.

To give an example, Mark Jurey's penny stove here has these stats:
Quote:
Fuel Use
15 ml. (1/2 oz.) of fuel will boil 2 cups of water. 20 ml. (2/3 oz.) boils 2 cups and simmers for another 2 min. or 10 min. with the simmer ring. At that rate, 8 oz. of fuel will boil 24 cups (6 quarts) of water then simmer for for 2 hours. Light the stove with the simmer ring on and 8 oz. will burn for a total of 4 hours - 12 fully cooked meals.
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Without a doubt, the hardest thing of all in a survival situation is to cook without the benefit of seasonings and flavourings. - Ray Mears

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