Go to Bitfinex
Log in or create a new account on https://www.bitfinex.com.
Follow to API
Hover the profile icon on the top right corner, then click API.
Click "Create New Key."
Name your key
When you have multiple APIs, a proper name helps to manage it.
Check "Write" on "Orders." Don't change other permissions.
Click "Generate API Key."
Confirm with 2FA
If you don't have 2FA on Bitifnex, skip this.
Confirm with email
Open the email from Bitfinex and confirm.