underwear bro, if you fail in citizenship interview then you will never pass any interview in your life because it's that easy. You have confirmed 100 questions and 100 answers. You can find it in youtube or you already have it as a booklet. You just have to give 6 answers out of 10 questions correct. If you give them 6 answers correct continuously then they won't ask you any further questions.
Do not sit in your chair while going to the interview room. Nepali haru ko muuuji somat chaina basa nabhanikana baasne basni. You have to be sworn first by the interviewer and they will ask you to sit. Then he will go through your DS 160 applications suchs a yes and no question. e.g Have you ever register to vote, have you voted , oath of aligiance etc. Just give the answer truthfully. It is better to go through your DS160 once again. Hope you have a copy of it.

Depending upon a USCIS office you may be scheduled for oath on the same day. So be prepare for long day. OATH takes more than an hour.

Do not wear jeans or underwear lol. Wear formal.

If you do not understand the question, ask them again and again. The whole practice session is in youtube. Watch those it helps a lot to reduce nervousness.
Since your interview date is Dec 16th I guess you can tell them our president is Obama (not trump)
Good luck. You can take your friends or family during oath ceremony because this will be very special moment and I guess it will be a turning point in your family history where you will be no more Nepali and become citizen of another country. You will be sworn that you will be give up all loyalty to your original country which is Nepal.