I don't think that their is exchange for newbies because you are expected to know how to trade or someone will do the trading for you. However, when it comes to trade their is no newbies but you can be newbies on bitcointalk rank. Some that just started investing in crypto should seek more knowledge about all it takes.
Every newbie can make an account on the already existing exchanges and there is no need for a separate account which would be recognized by the presence of newbies in crypto market. I think there is no need for a separate exchange as well because the purpose of an exchange is to provide facilities to the crypto users and that is already available on the current operating exchanges.