Schools should be the first place where proprietary software should be replaced with FOSS.
Microsoft understands the "get them while they are young" method very well, understands that it is a very significant element of the cycle that keeps them in power, and therefore puts a lot of effort into making sure that this does not change.
So getting children to learn on FOSS and the concepts around it would result in very significant changes, especially in long-term.

Is there any project or organisation that is already trying to achieve that?
If yes, then it would be good to spread the word about them around the internet.

Is that the same EU that wants to implement unilateral chat and sent photos surveillance?

Engadget/yahoo is fully enshitified. If you can read that article it probably means your browser is insufficiently defensive. A tl;dr bot would be useful here.

Ah yes all the child protection laws banning ETE encryption working right?

I don't know why my brain autocompleted that to "Microsoft secretly collecting children's dolls" but I like it better that way.

Maybe Windows devoting itself completely to being an advertising platform will be what finally takes it down.