You kick something when you hit it with your feet. A lot of sports are played by kicking a ball.
You kill something when you stop it from being alive. When a person kills another person on purpose, it is called murder.
Killing might also mean stopping something from happening, for example "lack of money killed his plans to go to Europe".
You kindle a fire when you first start it. The word kindle can also be used to describe something else starting, for example "a love for her was kindled in him".
Kneading is a way of mixing ingredients together to form dough. Kneading warms the dough slightly, and breaks the proteins in the flour down into gluten strands. When dough is kneaded enough it has a smooth, elastic texture. Dough that hasn't been kneaded enough won't rise as well when it is cooking, and will be hard instead of soft and fluffy.