I do have my oath ceremony scheduled for February 27th,2020 early morning I know that I will surrender my green card and get my naturalization certificate. my problem is next day on 28th i am scheduled to travel to Spain . I will use my Peruvian passport as identification will my naturalization certificate can help to enter to USA
Are you applying for dual citizenship? Are you renouncing your Peruvian citizenship once you take the oath for US citizenship? What is the exact scenario with your citizenship. If I am understanding your question, your current passport will become null and void. If you are not a citizen of Peru, you can not travel on a Peruvian passport.
You can, however, apply for an emergency US passport. Since you are a new citizen, I do not know how long it will take. As a born-citizen, my emergency passport took less than 8 hours. You will have to go to the passport office in person, as soon as they open for the day. That may mean delaying your flight.