How did the invention of the circle in performing during the neolithic era?

The Neolithic (/ˌniːoʊˈlɪθɪk/ (About this soundlisten),[1] also known as the "New Stone Age"), the final division of the Stone Age, began about 12,000 years ago when the first developments of farming appeared in the Epipalaeolithic Near East, and later in other parts of the world. The Neolithic division lasted (in that part of the world) until the transitional period of the Chalcolithic from about 6,500 years ago (4500 BC), marked by the development of metallurgy, leading up to the Bronze Age and Iron Age. In other places the Neolithic lasted longer. In Northern Europe, the Neolithic lasted until about 1700 BC, while in China it extended until 1200 BC. Other parts of the world (including the Americas and Oceania) remained broadly in the Neolithic stage of development until European contact.[2]

It helped with farming and Neolithic Age when they became a more settled people. One of the most important inventions was irrigation canals, which helped them water and grow crops which also made there population grow very fast!