Shamans are a hybrid class, which means they combine elements from two other classes (in this case, Oracle and Witch). They are also prepared casters, which means they need to choose which spells they are going to have access to at the start of each day. That could be a bit complicated for a new player, depending on how it works at your table.
What are the other players playing? Do you know if the campaign is going to be a published adventure/if so, which one?