What is the next step?

- When he must apply for Green card and does he needs to apply or he will get it automatically? Yes he needs to apply in one year counting from...

Yes your country of residence is the country you consider home. It is not the USA yet.

A friend in Brazil was denied a visa today. The denial was based upon fear of her not returning. What can be done?

Nothing. Rejections of visa under INA 214b carry no possibility for appeal. She can only refile with better evidence of ties to her country....

If I apply for divorce and leave country can I come back to USA again on same visa?

Filing for divorce does not invalidate your H4. Having the divorce granted by the requisite court does.

What is the priority date for Feb 2007 applicants and how much time will it take to get visa interview call and to be in USA?

You can check priority movement for all immigration categories on the visa bulletin site maintained by the US Department of State.

That EAD provides no permission to travel and none can be obtained for DACA recipients.

Can a mexican who marries a us citizen be able to petition her siblings?

Yes once your sister is a US citizen she can petition for her sibling.

How long after approve in citizenship interview it’s take for the ceremony?

Depends on the jurisdiction. IN some a few days, in others same day yet in others a few weeks.

You can refile the application again. There is no filing fee.

Can a priority date from an approved EB-2 employer sponsored be applied to a new EB2 NIW I-140/I-485?

Yes it could under certain circumstances which we cannot opine on since we have no idea about your circumstances.