N400 second/follow up interview?

No way of knowing if it is bad news. You must go to interview to finish processing. You should hire an attorney to review file and go with you.

You left out an important facf. What category were you originally approved in? If it was through a parent who was a green card holder you became...

Detained in another state?

You can hire an attorney in NY. He migjt be able to help get your relative out on bond and move the hearings to NY.

How to input household size in I-864 Part5 when sponsoring own spouse for I-485, as the total becomes 3 instead of 2?

I usually put a dash in item 3 and put an arrow up to 1 where you counted wife.

You cant file I-485 when you are in Canada.

Does the ban effect me as well?

Because of your age at the time you are not statutorily barred and can apply for visa/entry. Having said that they have the discretion to say no at...

Is there any chance to get the 10 year_green card?

Yes - you need to file I-751 with divorce cert and all evidence of the marriage while it lasted.

Can I travel with my green card abroad if it expires in two month ?

If you are back before it expires or you could apply for a renewal card by filing I-90 and then getting. A stamp at local USCIS office.

Speed up individual court hearing date

Speak to your lawyer. He may be a me to arrange to switch date with another case/lawyer.

It means you applied for your adult unmarried son and the filing date is the priority date, and place in line. It will take several years to process.