[Sundae]

If I had that crazy amount of money, I would want to set up some community housing complexes.
Helping people who can't quite manage alone, but aren't far gone enough to require medical assistance day to day (wonder where that idea came from?)

There would be some sort of attendant facilities for people to work. Well, "work" to start with. Coffee shops or farms or animal sanctuaries, where they could build self respect and skills alongside the professionals who really were running the show. Obviously every charity (because it would be, for tax purposes) also needs office staff, book-keepers, chefs etc, so it wouldn't simply be channelling people into minimum wage work.

They would be a safe place for people to recuperate and get back on track.
And I'd pay the staff very well, so they also had a positive experience from their potentially challenging roles.

It wouldn't change the world. But it would save a few lives and change a few which had become unmanageable.