How to start cryptocurrencies trading?

How to start cryptocurrencies trading?
For beginners in steemit

1. Find a cryptocurrency wallet and good exchange to do the trading.
2. Wallet is needed to store your encrypted passwords which is in real life coins.

The cryptocurrency exchange is where you buy and sell these digital coins. And since I am new I did some research and found these famous names to start with.
List of the exchange or broker
GDAX it has the lower fees
Coinbase : mostly used in USA
Cointree
Bittylicoin
Coincorner : mostly used in UK

I have no experience but read good reviews about these exchange.