I’ve made a few blog posts about cryptos, bitcoin in particular, with it’s proof of work. Now, I want to go into POS.  

When one buys a POS coin, they have the option to hold it in a special wallet, for a set time. During that time, you don’t spend/trade it, but leave it be, in exchange for some returns in the form of interest. After the staking period, you get your coins back, plus whatever interest. If you have thought about crypto, perhaps you should look at staking.  

Beware that some coins, you may not be able to get through coinbase. Further, as rules are changing, more and more exchanges may not allow US investors, or may not allow US investors from some states.