A good kitchen knife: It doesn't have to be expensive. You can look up commercial kitchen knives for an affordable workhorse. Or spend a little more on a nicer one. Look up the brands some professional chefs use. I wouldn't recommend buying a knife block set.
Sharpening stone: There are many types of sharpening stones. You can start with a cheap set that covers many grits or get a King combination stone. There are also more expensive ceramic and diamond stones. You can sharpen many things with a stone. A sharp edge is a safer edge usually.
A cast iron pan, a stainless steel pan and an enameled Dutch oven. A cast iron pan will last you your whole life. It can cook sear steaks, entire meals, bake cakes, shallow fry. It doesn't do well with dishes that contain a lot of acids. Cast iron can be very affordable or expensive. It's just iron. For acidic dishes a stainless steel saute pan will work well. It should also last your whole life. With an enameled Dutch oven you can braise dishes, makes stews, soups, bake bread and deep fry. If you make sure to not damage the enamel, it will also last your whole life.
A cookbook that covers multiple cuisines. Usually if it has a chefs face on the front I'd stay away. They are celebrity chefs trying to make money. Often their dishes suffer for it. Try for something that has classic regional recipes.
Learning how to cook will give you a valuable skill, way to relax, keep you healthier and will help you save money by feeding yourself. It can help you be sociable by cooking for others and maybe impress a special someone.
A Leatherman multi tool. There a lot(too many) options to choose from.