1.  Create an OpenAI account at https://platform.openai.com/signup  or sign in if you already have one.  
  2. Navigate to https://platform.openai.com/settings/organization/billing/overview, then click "Add to credit balance". Adding $5 (Tier 1) is enough for most cases. Learn more about tier vs rate limit.

  3. Navigate to https://platform.openai.com/api-keys, then click Create New Secret Key.
  4. Click Create Secret Key. Optionally, you can choose a name. You can select All or Restricted for permissions, with at least Model capabilities set to write.
  5. Click copy on the generated key.  Important: Keep your API Key private. Please do not share it to avoid unauthorized use.
  6. On the Add-Ons, go to Settings --> API Key Settings. Paste the value, then click Save.