You can use "Somebody"\"Someone" in questions, For example you might say "Did someone drop a penny?", Although there are different implications, To me atleast if you ask a question using "Someone", Then the only people who could be referred to by the "Someone" are the people you're talking to, While "Anyone" is more general.
I am not a native, but I believe it is "qualcuna" because the speaker is asking a group of females. The sentence could equally read "A qualcuno piace questa ricetta?" if the speaker were asking a group of males. The gender of "ricetta" has nothing to do with the choice of "qualcuno" or "qualcuna". Please correct me if my interpretation is incorrect.
As you know, someone, somebody, anyone, anybody, nobody and no one all get wrapped into qualcuno and nessuno. DuoLingo is not able to make these distinctions; just a limit we have to live with. The system gets tripped up on word order too, once in a while. There can't really be someone there, a native speaker or a true expert, who can be making these decisions, do you think?