Is it a cultural difference with Europe (and other parts of the world) to not go in the streets?

Yes, it’s not like it’s entirely unheard of here in the USA (look at what happened with the killing of George Floyd) but for systemic issues, it doesn’t generally get people in the streets, I think at least partly because there’s so many we’ve put up with for so long. There’s also the economics of it where we have less or no time off from work to get out for such events.

Are those occurring but the medias do not inform us on it?

There are protests happening but there does seem to be, putting it charitably, a lack of interest to report on such things, and the protests that are happening don’t seem to be of very notable size (again, that could be media spin).

Are people scared to protest?

Yes, I imagine plenty are, especially those who may be targeted by ICE or have friends/family who may be targeted by ICE.

Or, people just don’t care or are even, in majority, happy with what happens now?

To an extent, yes. I don’t know if I’d say that the majority are happy with the things happening, but a majority are probably okay with it, or just going along in ignorance (willful or otherwise), or too busy or tired just trying to survive rather than make things better.