The classic question of WWYD if you won an obscene amount of money BUT, let's assume you've enriched your whole extended family, bought your dream house/car and saved all the donkeys/built wells across the deserts/funded your favourite charities for life.
I want your BIG ideas, your dream projects, your fantasy businesses, the mausoleums dedicated to your pets, the toilets carved from marble etc.
Me first...
I would buy plots of land in my city and knock down the buildings(assuming derelict) and plant urban forests.
I would build a whole self-sufficient miniature eco community where my SEN child could live and work looking after the animals/farm
I would hide my massive windfall by pretending my little ldt company suddenly became wildly successful and would buy premises and staff it and would use it to design and administrate the above projects and more similar ones.