connected service

Hi Srikanth

Your questions is very light on detail so it's difficult to know exactly what it is you're trying to achieve.

From an abstract point of view:

1. You create Connected System objects as stand-alone components, so that you define a remote system once and can re-use it many times: https://docs.appian.com/suite/help/20.1/Connected_System_Object.html
2. You can then create an Integration object that makes use of that Connected System: https://docs.appian.com/suite/help/20.1/Integration_Object.html
3. And finally you can make use of that Integration object in a Process Model by referencing it from an Integration Smart Service: https://docs.appian.com/suite/help/20.1/Call_Integration_Smart_Service.html

I need to upload an image from the interface to google cloud.

for that google cloud, I created a connected system.

so for uploading an image, I need to use the existing connected system in-process model.

You can't directly use a connected system in a process model. A connected system only defines the configuration of how to connect to the external system - in your case the connection information to Google Cloud. As Stewart said, you will also need to create an integration object. This is the place you set up what operations you want to do with the external system and what variables you will use. Then you can use the integration in your process model.