A jetty is a structure that sticks out from land into water. Jetties can be made of stone or timber. Sometimes they are there to protect the beach from waves, sometimes they are built to reach deeper water so ships can dock.
A machete is a kind of large knife that is used in tropical areas to cut through jungle or to harvest sugarcane. It is also used as a tool for cutting up food, or for carving wood.
Because machetes are so common in tropical regions they are also used as a weapon.
Variety is a way of saying you have lots of different things. Often you talk of variety between lots of similar things, for example "there was a wide variety of fruit available". The picture is of a variety of spices for sale at a market.
A Yeti is a hairy, human-like creature said to live in the mountains in Nepal. Yetis are legendary creatures, but it hasn't been proven either way that they exist or are just a myth.