You have to see what kind of person you are and how you come to know things. I will explain why and how.
The why is related to "why do I trust certain things and others not?" "why do I believe certain things and others not?"
Are a "rational equirer" kind of person? To which degree are you influenced by the people around you (we all are)?
I say that because *I am* a rational enquirer kind of person and examining alternatives does not cause any discomfort. Indeed, I analysed many religions and christianities before becoming Orthodox. I was even Kardecist for some time. *For me* it is part of the process of learning, understanding something.
The point is, for you, would it do any good? Is that how you learn, by comparisons? Remember that today many people think that comparisons are offensive (particularly if you must make a judgement of "better/worse" or "right/wrong" in the end).
To learn if that's the case for you, try to remember the things that you know that you know, that is, not the things you are sure (a feeling) that you know, but that you know as fact that you know them. Don't use the big questions for that. Do you know who your mother/father is? Do you know you love a person? Do you know that you are good at music?
After that, analyze *how* you came to know these things. Did you go through a thourough analyzes of all the alternative possibilities? Did you just "dived in" to learn? Do you know that because you trust people who told you that you know it? Do you know it because you analyzed all the constituent elements? Do you test your knowledge by experimenting? How do you come to learn the things you know that you know?
Just use the same technique with Church.
*My* way is to start by forming a mental map of the scenario in study and from this kind of "table of contents" of subjects study each element and rearrange them in the map as I learn more. I have great difficulty if I have to start from "bottom-up" with elements devoid of context. That is why "I" had to learn about a couple of religions before I could say I understand at least one of them. *I* would not consider that I know any religion in particular if I could not see it in perspective with other religions, what they mean to each other. That's just how my "brain software works". Maybe that is how your friend works as well. Is that how *you* work?