1. Go to integrations. You need to create an integration from your store admin, click on System > Integrations.
2. Create an integration. To create an integration you must first click on the Add New Integration button.
3. Complete the information. In this step you should complete the information, for Callback URL and Identity link URL please copy this URL https://oauth.ecartapi.com/oauth/magento2/access/NrUAVHsfjTJUE0NacgA7mVSogkfTuWTW, before click on Save see the step 4.
4. API settings. Please change Custom to All option in Resource Access field and click on Save button.
5. Activate. Now you can see the integration created but you need click on Activate, after click on Allow button to finalize.