Bitcoins are stored in a wallet, which you can use to buy, sell, or send bits or whole bitcoins to anyone, anywhere in the world. Blockchain is the world’s largest bitcoin wallet provider.
You can quickly and easily set up a secure Bitcoin “bank account” without storing the data on your computer. They do everything for you, and their security is top-notch.
Simply follow their recommendations when setting up your wallet.
Especially the bit about the private key, which should be written on paper and stored safely. They also provide you a mnemonic phrase, which should be stored safely separately from the key. Consider it a backup.
In addition, I strongly recommend you set up a Google Authenticator account on your phone and tie your Blockchain Wallet to it. If you do all of this, your bitcoins will be very secure.