Dr. James White has a little article with an excellent graphic of an ancient manuscript of P-72
which has both I and 2 Peter (and Jude) in it. One of the pages of this manuscript shows the end of 1 Peter and the beginning of 2nd Peter and this manuscript called P-72 is dated at around 200 AD. That is very good early dating for a copy of one of the most attacked books of the NT by skeptics, atheists, and Muslims and others, sometimes by good scholars. (the Muslims like to use Bruce Metzger as authoritative evidence that 2 Peter was not written by the apostle Peter. But many other conservative scholars and all Christians who believe in inerrancy believe that 2 Peter is "God-breathed" and was written by Peter. ( 2 Timothy 3:16-17; 2 Peter 1:20-21)
So what about scholars like Bruce Metzger and Ben Witherington III? Are they wrong to conclude that Peter did not write 2 Peter? I'm not sure. Does that mean that they are going to hell ("went" in Metzger's case given that he died) because they did not think that Peter wrote all of 2 Peter? Nope. What one believes about authorship is not a litmus test for orthodoxy. What is important is what you believe about Jesus - is He Lord of your life or not? Do you accepts his propitiatory sacrifice on your behalf and live submitted to Him? That is how you know you are born-again.
I highly recommend this article and hope that anyone who has doubts that Peter wrote 2 Peter or that the Bible is in anyway reliable will read this article along with their own research for the truth.
Beggars All: Reformation And Apologetics: Good Evidence for Historical Reliability for 2 Peter as written by Peter Himself