where should i invest and why ?
Do your research and invest in most promising tech, you can find all the tokens/coins listed on coinmarketcap. diversified investment is the best way to go and never go all in, keep some % dollars in reserves, in case something goes wrong/you need some money urgently.
$500k to invest? Wow you're a baller! I would put it all all Dogecoin. Go the Dogeeeee!