There are a lot of platforms where you can buy and/or store cryptocurrencies. Here's a good overview: https://coinmarketcap.com/rankings/exchanges/
You can use a web-wallet (an exchange-/broker-account), a software-wallet (an app) and/or a hardware-wallet (a USB- or Bluetooth-stick) to store/hold your cryptos.
I don't really know where to put this but I've been looking at doing some basic mining.
Currently got BTC running but it's only a tiny amount every day.
Is there something that has a better return?