After configuring the settings, you can “sign-in” with a non-Dynamic JWT token by calling the signInWithExternalJwt method from the useExternalAuth hook. 
const { signInWithExternalJwt } = useExternalAuth();

try {
  // `externalUserId`: User ID in the external auth system
  // `externalJwt`: Raw encoded JWT issued by external auth system
  const userProfile = await signInWithExternalJwt({
    externalUserId,
    externalJwt
  });

  if (userProfile) {
    // You should be logged in at this point
  }
} catch (e: any) {
  console.error('Dynamic login failed:', e);
}
After this point, you can use the Dynamic SDK to access the user’s profile and other data, just as you would with any other user.