Yes, they are the same. Pauwi is just a short term of papauwi.
But sometimes, "pauwi" is just a straight meaning you are on the way home while the "papauwi" you can add something you did while on the way home.
ex.
1.Pauwi na ako. - Im on the way home.
2. Papauwi na ako ng makita ko ang aso. - I'm on the way home when I saw the dog.
Keep learning. :)