Invest it. I don't know why. I have lots of money sitting in my bank account but it doesn't change anything. I am miserable. I don't want anything.
I have 2 kids and buy them expensive things. I'm not sure I'm doing them any favours though. They have no idea about money and they are teenagers. They don't appreciate things. I bought my 17 year old a condo in a large urban centre close to a university. He decided not to go there.
Back in my 20s I bought a vacant building lot on a small lake. We built a beautiful cottage. (Meaning I hired people to build it) It was the happiest time of my life. However my husband hated it. So a few years ago we sold it and then he went and bought a really expensive sports car. That caused me anxiety and the downward spiral in both my physical and mental health.
If your asking for advice - invest in yourself. Be it an education, career, health, spiritually, or a place where you feel truly at peace.
However if you are done investing in yourself, give to charity or blow it on the thing you really needed before you die. I don't have that "thing".