You have a few options for configuration and deployment of a telemetry ingestion pipeline, depending on what type of connectivity is preferred between the IOS router and the Telemetry Collector.
gNMI Dial Out connectivity
If you are connecting from the router to the Telemetry Collector via gNMI Dial Out, then you choose between the easiest instructions (which leverage User Interface functions for building the componetns)or the someowhat more difficult API instructions for achieving the same thing, but will require the user to understand how to issue API calls from a tool like postman.
Option 1 (recommended because it is the easiest): IOS XE and XR via gNMI Dial out - UI method (Easiest)
Option 2 (API method) IOS XE and XR via gNMI DIal Out - alternate API method
gNMI Dial In Connectivity
If you prefer to leverage gNMI dial in connectivity, these configuration is not available in teh UI, and must be achieved via APIs and configurations files, as described here: IOS XE and XR via gNMI dial in - API method only