Sugarcane can grown in certain climates and can be cut, peeled and tasted. It is then squeezed to make cane juice. To make sugar from the sugarcane that you buy in the grocery store, it is processed in a factory. Depending on the treatment it becomes lots of different types of sucrose: powdered sugar, granulated sugar, evaporated cane juice, molasses, brown sugar.
Sugar beet is grown in temperate climates with the root underground that has sugar content. It's very similar to the sugarcane which heads to a factory to get processed into the same sucrose varieties.
Miracle Berry grows on a tree originally from West Africa. When you eat the berry, also called Miraculin, sour foods taste sweet for about 30 minutes.
Stevia is a small plant like an herb where the leaves can be used directly as a sweetener. They taste sweet and can be used in tea and smoothies. Typically when you buy it in he store, it is made with chemicals and refined and only safe until further research to eat the leaf directly.