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

Freedom of speech does not apply to:

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.

And much, much more.

Study Reveals Plague's Evolutionary Hack to Survive 3 Pandemics - ScienceAlert

Threats of violence

Perjury

Insurrection

650-Foot Mega-Tsunami Shakes the Planet, Sending Waves Across Continents – Satellite Footage Shows the Destruction - The Daily Galaxy

No freedom is absolute.

False advertising

Terroristic threats

What’s the best way to monetize email subscribers?

Trade secrets

Revealing classified information

Revenge porn

Why does Microsoft always create so many ugly, confusing, and ridiculous product names? The worst of them all is ".Net" (which is really confusing).

Conspiracy

Insider trading

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.

Do many women shave their vaginas?

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.

Fraud

Child pornography

When the mind leaves the body - scientists investigate the incredible phenomenon of OBEs - Earth.com

HIPAA violations

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.