It should go without saying that if you're going to become Peruvian you should learn Spanish. You'll be treated differently than if you speak English all the time, it'll help you assimilate to Peru, and it'll get you cheaper prices. If you're looking to learn Spanish, check out Fluenz Spanish, Rosetta Stone, and Synergy Spanish.
When I was in the naturalisation office I had to deal with people who told me I HAD to change my name, yet a friend of mine didn't. Actually, no man I know has had to change their name, seems like only women do. In addition, everyone there was there because they were Peruvians born abroad and were trying to get citizenship. This was back in 2008. Now I've been told things have changed.
Once you become Peruvian, you'll have to assimilate to the Peruvian culture, so if you don't know enough about it, I highly recommend studying up on it.
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