Thanks @Damiores I was asked about my qualifications, the kind of work I do, US travel history, if I have a job offer (not a requirement to have a job offer, but will be good to start applying to jobs), what I plan to do in the US, where I plan to stay.
Be sure to go with your CV, and in my case I went with my Google scholar page to show my publications.
Some of the visa officers are not familiar with NIW category so be sure to go through your I140 petition and be familiar with it.
It wasn't anything tricky and you should be able to answers the Qs asked easily. Hope this helps.