If freedom of speech is absolute, how come it's not applied for private spaces and for the Internet?

That’s what it is. You have no right to use other people’s stuff. If people let you use their stuff, they can tell you how you can use it, and they can tell you to stop using it any time they want.

False advertising

Freedom of speech does not apply to:

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You have freedom to travel. If I loan you my car, I can tell you not to take it out of town, because it’s mine, you have no right to use it, and if I give you permission to use it I can tell you what you can and can’t do with it.

Child pornography

Conspiracy

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No freedom is absolute.

Threats of violence

Insider trading

Is it accurate to say that while Donald Trump has "America First" policy, the Democratic Party has "Other nations first" policy?

HIPAA violations

Perjury

Revealing classified information

Who is Meghan Markle and why is she so controversial on the Internet?

You have freedom of speech. If I loan you my computer, I can tell you not to use it for certain things, because it’s mine, you have no right to use it, and if I give you permission to use it I can tell you what you can and can’t do with it.

If you’re wondering why free speech doesn’t apply to the internet, it’s because you have no right to use other people’s stuff for free.

Insurrection

Can cheating be a result of not truly loving or caring for someone, or is it sometimes just a spur of the moment decision?

Trade secrets

Fraud

Revenge porn

What is something you want to "get off your chest"?

Terroristic threats

And much, much more.