Apart from the ones listed where there are restrictions due to ranks, you are free to express yourself in any board you are comfortable and have knowledge to share, however as a newbie, in your early days especially if you are new, with little knowledge about crypto and have never been in any forum, the most appropriate board where other forum users here expect you to have more activity in is in this BEGINNERS & HELP board where you can gain visibility before you begin to try out discussions elsewhere. But say you are an experienced newbie with very good knowledge of crypto, particularly bitcoins and that was what lured you to sign up here, you can participate in Development & Technical Discussion and Bitcoin Technical Support.