For someone who is ready to explore the forum themselves without being told a local board exist will definitely find out there are sections for that, but it should be noted that participating in them is by choice, you can always maintain being on the English boards,
It's not in the forum rules that it's mandatory for everyone to post on the local board, and nobody is forcing anyone to post there, it's just a matter of choice. If you don't want to post there, then you are not forced, and if you are interested in posting on the local board, that's also not a bad idea. Not all countries have a local board on the forum here, so if you are from a country that does not have a local board here, you don't have a choice but to maintain posting on the English board.
If a newbie is not good at speaking or writing in English language then the local board will be useful since the language that is used is your own language before you can join other discussions that are not in your local board (after learning English). If a newbie already knows English then there's a thread called Beginners & Help and there's also a thread that Ratimov have created where different topics are in there for newbies to check called Beginners & Help Encyclopedia.
Local boards provide many benefits and are intended for all ranks, not just beginners. They are not for persons who cannot speak English effectively alone. Because some local events, which might be very helpful to both high-ranking and low-ranking members, are only posted on your local board and aren't always posted in other sections of the forum, I said that the local board is not just for people who don't speak English fluently. You have to be aware of local events as they happen.