You can create multiple APIs, Name each API accordingly so that they are identifiable and can be managed accordingly. A passphrase is needed to create the API, this is not the account password and can be set individually for each API. Under permissions, please check that Trade is enabled.
Once the API is created, click on view. To view the newly created API you'll need to authenticate with a secondary verification method via Google Authenticator or SMS.
Use the scan QR code function on CryptoHero to add the API immediately or if you are on the same device, you can use the copy and paste function for both the API Key and the Secret Key. OKEx requires you to enter the passphrase used to creating the API in CryptoHero.