According to Lumen Learning, “The Estates-General of 1789 was a general assembly representing the French estates of the realm summoned by Louis XVI to propose solutions to France’s financial problems. It ended when the Third Estate formed into a National Assembly, signaling the outbreak of the French Revolution.” So the third estate began the French Revolution by forming into the National Assembly, and that signaled the beginning of the French Revolution.
According to Wikipedia, “The French Revolution was a period of radical political and societal change in France that began with the Estates General of 1789 and ended with the formation of the French Consulate in November 1799.” The French Revolution lasted from 5 May 1789 – 9 November 1799. The French Revolution began when the Estates General was called because of a widespread economic distress in France. This became radicalised by the struggle for control of public finances. Shortly after the Estates General was convened at Versailles, the Third Estate met alone and formally adopted the title of National Assembly. Three days later, they met in a nearby indoor tennis court. It was there that they took the Tennis Court Oath, vowing never to disperse until constitutional reform had been achieved. A little while later, we have the Storming of the Bastille, and then the Declaration of the Rights of Man. Then the king was executed, and the Reign of Terror began. Then we have the Thermidorian Reaction. Eventually, Napoleon Bonaparte came to power, and ended the French Revolution and marking the beginning of the Napoleonic era.