Is Centro Rio safe? Booked AirBnB

Hi,

Me and my girlfriend are starting out backpacking trip in Rio and spending the first couple of days in Centro, on Ria Alcindo Guanabara.

It was a last minute decision as we were only going to go to Spanish Speaking countries as and we don't speak Portuguese.

Basically wondering is it safe? Any recommendations on food and nightlife would be massively appreciated.

Thank you!