About domain name of Box API_2

I have an additional QA following QA

https://support.box.com/hc/en-us/community/posts/4407367190547-About-domain-name-of-Box-API

1.
I'd like to make users input ID/Password every time when oAuth API is called 
Is there method in box API??

2.
Also is www.box.com/oauth2/authorize out of supporting ??
If possible, I wanna use this API due to ID/Password is shown every time even if authentication was passed last time