The State can prove a DWI by 1 of 2 ways. That your BAC was .08 or higher, which wouldnt apply in your case obviously, or that your mental and physical faculties were appreciably impaired. This is proven through the officer's observations of you ie your driving, field sobriety tests etc. I often argue to the DAs that if they live by the sword, they should die by the sword, meaning if they always move forward when its .08 or higher, then when the blow is below a .08, they shouldnt proceed....
Absolutely consult with an attorney. You are looking at a possible misdemeanor conviction for an offense involving honesty. Most future employers will pass right over you if they find out about it. There may be several options at your disposal to keep this from happening. Talk to a lawyer asap.
Its called an underage DWI. It is a serious misdemeanor offense and if you are convicted, you could lose your license for a year, just like a regular DWI. Plus the conviction will follow you around and you may have to explain it to future employers, etc. I recommend consulting an experienced DWI attorney in Charlotte. There's too much at stake not to do so.
My best guess without seeing the judgment is that the sentence was suspended since you were put on unsupervised probation and you arent in custody currently. If you do not abide by the terms of the probation, then they may activate the sentence. Keep in mind that if you do not like the sentence, depending on which court you were in, you may have some appeal rights but you only have a limited time. Contact an experienced criminal defense attorney if you would like to explore those rights.
No. You will be required to install the interlock in your car before DMV will reinstate your license a year down the line. There is no way to get around the requirement. If you decide not to drive for 10 years then get your license in NC, it will still be required. Only way around it would be to move out of state and become licensed there.
If a judge dismissed a DWI for a pretrial motion made by your friend's attorney, such as lack of reasonable suspicion or lack of probable cause to arrest, then yes, the State can appeal that to a Superior Court judge. Sometimes they do appeal, sometimes they don't. Obviously, if they appealed your friend's case, they think they can win it. They can't appeal an actual finding of not guilty, however. Just a pretrial motion.
You need to speak with an experienced DWI attorney. In order the avoid the IID, you need to beat the charges. That said, the officer needs to have reasonable suspicion to investigate you for DWI. Ive included a video on that for your convenience. Talk to a lawyer asap.