Here is a TOP 10 for the best Cryptocurrency Exchanges :
http://www.crypto-side.com/2018/01/the- ... in-or.html
You will find :
-Fiat Exchanges, where you can buy Bitcoin directly with dollars or euros.
-Alt-coin Exchanges, where you can trade your Bitcoin to other crypto-currencies.
-Peer to peer Marketplaces, to directly trade Bitcoin, without a third-party.
All with details about how to register and how to buy your Bitcoins and Alt-coins.