Just a few notes before picking your desired exchange:

Please do note that before you choose your exchange, look for one that has the lowest exchange fees. All exchanges have fees in every transaction and this may cause a fortune especially if the exchange is relatively new.

Another thing, security is very essential and collateral. Ever since what happened to coinbase a few years ago, I migrated to our LOCAL exchange and put almost all of my BTCs there in order to prevent such from happening again.