Brazil Carnival 2027

Hello r/Brazil. We are a friend group of four 21 year old guys planning to visit Rio and Sao Paolo for the 2027 Carnival season. We are planning on staying for 2 weeks (6-20 February). We would really appreciate some help regarding some things like when is the best season to book tickets from Europe, areas we should book BNBs, what the weather is like that time of the year, where to go and what to do to live the actual authentic Brazilian lifestyle and not the touristy sh*t. Unwriten rules, how many days we should stay and what should we see. How chaotic is the carnival? So many questions that need answering soon cause we have to start planning I guess. Thank god we don't need to apply for Visa.
Thanks in advance 🇧🇷 🇬🇷