You should create a Bitcoin wallet first. You can download a software wallet, buy a hardware wallet, print a paper wallet or use online wallets.
I don't suggest you to use online wallets because they don't give you your private key so you don't have full access to your wallet. Paper wallets are private keys printed out on a piece of paper. You can only recieve Bitcoins and can't send Bitcoins without importing the private key to another wallet. If you are dealing with large amounts of Bitcoins you will need a secure wallet because they are securer than the others. If you aren't, I advice you to use an software wallet. It is easier and cheaper.
I use and suggest you to use Electrum. It is an easy to use.
You can have more information about wallets from this topic:
https://bitcointalk.org/index.php?topic=1631151.0