Answer:
Isaac Newton did not invent gravity. Gravity is a fundamental force of nature that has always existed. Newton's contribution was to formulate the laws of motion and universal gravitation, which helped to explain the behavior of objects under the influence of gravity.
As for how people flew before the development of powered flight, they relied on a variety of methods, such as gliding, using hot air balloons, and being lifted by the wind in kites. For example, in China, people have been flying kites for more than 2,000 years. In the late 18th century, the Montgolfier brothers developed hot air balloons, which allowed humans to ascend into the air for short periods of time. And in the late 19th and early 20th centuries, pioneers of aviation such as the Wright brothers and their contemporaries developed powered aircraft, which eventually led to modern air travel.