Simon Bolivar is the name most closely connected with the liberation of South America. As you say, he is known as the liberator of the continent.
Although he is known as the liberator of South America, his importance is actually limited (if you want to say it that way) to the northern part of the continent. He was the leader of the rebellions that liberated the areas that are now Colombia, Ecuador, Venezuela, Bolivia, and Peru.
As far as how he helped his people, that's up for debate. He did lead the wars for independence. But he later became disillusioned with how the new countries were behaving after becoming independent. So it's not clear he would have said he helped the people at all.
So -- he led the liberation of the countries, but beyond that it's not like he ruled any of them for very long or led them to stability or prosperity after they became independent.
When Bolivar was born in 1783, South America was under the grip of Spanish rule. Bolivar, born in Venezuela and the son of a wealthy family, was educated in Europe and there learned the Enlightenment ideals of liberty and equality. Upon returning to Venezuela, he led his country to liberation from Spain and thus to its status as an independent nation-state. He was also instrumental in gaining independence for Bolivia (named for him), Peru, Colombia and Ecuador. For this accomplishment, no mean feat, he is known as The Liberator.
As is often the case with former colonies, however, these countries gained independence and soon turned not into the democratic republics envisaged by Bolivar, but into authoritarian regimes which left the common people little better off than under Spanish rule. This led Bolivar, who died relatively young, to feel some despair at the end of his life. He brought freedom from Spanish rule to parts of South America, but not freedom from tyranny and oppression.
Simon Bolivar (1783-1830) is called El Libertador (The Liberator) by people of Bolivia, Colombia, Ecuador, Peru and Venezuela for liberating these countries from Spanish rule. He fought the Spanish armies in various capacities from 1810 to 1824 to end Spanish power completely in South America in 1824.
Bolivar became a dictator of Peru in 1824. In 1825 Upper Peru separated from rest of that country, which was named Bolivia in honor of Bolivar.
Simon Bolivar wanted to establish a union of South American states on the pattern of the USA but failed in his attempts. A feeling of resentment against him grew among many people and he narrowly escaped assassination.