Alike is when some things are all very similar. The two girls in the picture are dressed alike.
Bike is short for bicycle. More people use the short form bike than the long form bicycle.
A hike is a long walk, usually through fairly remote or wilderness areas. The person in the picture has hiked to the top of a mountain.
A motorbike is a two-wheeled vehicle powered by an engine, the same as a car is. Motorbikes come in a variety of sizes and speeds, but usually only fit one or two people.