You could and you couldn't. You could because there are recipes that are that old and you could perhaps even use the same cooking methods if you happened to have a big wood-burning fireplace or access to a wood-burning stove. You can't because the recipes of this time do not often include particular amounts of ingredients. They were intended as an aid to memory for cooks rather than as a complete guide to replicating a dish. Modern recreators of the recipes have had to guess and experiment to figure out what proportions of ingredients seem to work but it's unlikely they get it exactly right. There is another sense in which recreating these exactly is difficult to impossible. Many of the ingredients have changed a bit since 1450. Selective breeding, changed tastes and changed agricultural practices have resulted in foods that are different from what they once were. Just as an example, chickens are radically different from what they were just fifty years ago. They have a different diet, generally move less and are killed younger than they were in the past. While if you tried really hard you might find an older free-range chicken for sale of a breed that's kinda-sorta like a medieval breed this would be impossible to do for most foods.

You would likely be fine eating things preserved in the usual medieval ways of salting, pickling, drying, smoking, fermentation and confit (meat stored under solidified fat). All of these kill problem-causing microorganisms.