Houses, cars, and other big stuff generally need time to search and think, so I guess the first thing I would do is go to the fanciest supermarket and buy all those expensive food that I never bought. I think one of the biggest benefits of being rich is eating whatever you want, not worrying about the price of your breakfast/lunch/dinner. Obviously I would go out to eat but eating well at home is such a great thing.
Would probably buy a bunch of smart home tech because they are expensive and definitely not worth the price right now, BT if I were rich I wouldn't even care.