OKta + react native + OKta custom login page + okta login in offline

I have a react native ios app to which I have integrated OKTA but I also need a OKTA custom login page directly in my app so that the user will not redirect to okta page to login.
Can I use for integrating login page into my native app or any other packages/dependencies should I download and also can we make a user login in to okta when he is not connected with internet.