Is it true that in US you can be jailed if you will say the N-word to some black person?
Because I heard some stories from some people and I really doubt but still I really not know much about the U.S. laws (and about it's states laws, of course).
No, it's not technically true. Though going up to a person and insulting them might be considered threatening or menacing behavior, precipitating into a conflict. You can't pick a fight with somebody and then claim free speech, especially if you choose fighting words. And verbally assaulting people on private property is going to be handled by the property owner (e.g. kicked out by security guards).
However, it's incredibly disrespectful and rude. It may result in the loss of jobs and even friends.
But it is not akin to Holocaust denial in Europe or blasphemy in the Middle East. You are free to say the word, privately or publicly, without fear of arrest (or at least the First Amendment ought to have protected your expression). But you can't incite a brawl with a racial slur and point to the First Amendment.
In the US?
Freedom of speech, the first amendment, only means you are protected by law from legal prosecution/persecution for saying disagreeable things.
You can certainly deny the Holocaust, or 9-11 or say the N-word (as a non-black person), but it doesn't mean you can say that stuff without consequences.
But the rules are far more complicated than a foreigner might imagine.
The consequences of anything you say depend on who you are and when you say it.
The rules actually change from day to day. What is acceptable yesterday, may not be acceptable tomorrow.
And what is unacceptable today MAY be acceptable tomorrow. It is really hard to say for sure.
This is why even professional pundits get into trouble ALL the time.
Usually, saying the wrong things often means getting fired from one's job, and becoming unemployable (for an arbitrary amount of time. For example, Bill O'reilly is still unemployable. As in Megyn Kelly. They have to wait until the internet has forgotten them... ).
These rules are very complicated, and basically anything can offend someone.
If you are afraid of running afoul of these rules, it is best to say nothing at all.
Here are a few examples of what can happen...
This stuff happens to regular people too, some times over comments made long ago.
This one I believe is an example of the n-word... that was just in the news a few weeks ago
If you are an independently wealthy recluse, you can say almost anything without any consequences. The government still observes the first amendment. and if you can withstand the societal backlash, you have nearly total free speech freedom. (you still can't shout fire in a theater)
No, but you might get punched out, and the person doing the punching might not get charged with assault... the reason being extreme provocation.
There is expressing one's opinion, and then there is insulting purely for the sake of insult. Freedom of speech does not relieve one from the responsibility for what has been said.
Ironically, there are a number of racially charged terms with origins in the US that aren't said any more because they've been forgotten or no longer have any meaning. One example is 'chinaman'... once considered to have the same connotations as other racial insults: labeling a person as inferior or subhuman.
That term isn't used any more because Asians have thoroughly disproven the implication.
It's a pity that all racial insults can't expire like that.