Hi there,
The meaning of Freedom of Speech is to know what the people (community) in local states or countries have to say, like when it comes to voting or regular politics they want to hear the people's voices and see what they are comfortable with or how certain things they might vote on affects their lives and the whole state.
Freedom of Speech is a part of the Constitution in fact, it is the First Amendment. it says: Congress shall make no law respecting an establishment of religion, or prohibiting the free exercise thereof; or abridging the freedom of speech, or of the press; or the right of the people peaceably to assemble, and to petition the Government for a redress of grievances.
So, Congress cannot pass any law without the people's voices or approval then they have to pass it onto the president for the final signature.
That is what Freedom of Speech means
Hope this helped
Have a great day :)