I m building one web app using the ringout api .I just want to know is there anyway using which i can get the access token without redirecting the application user to ringcentral website from my application .
I still don't fully understand your use case. But if you would like to get the access token without redirecting to RingCentral authorization page then the only choice is to use the password flow authorization for your RingCentral app. With that, you can get the access token from your Web app server code and use e.g. the session to pass the access token to the client side.