But I do know which is right
The answer is very easy.
Jesus clearly gives the "keys of the kingdom" to Peter Alone - a role we know from the OT is a "prime minister" type role with succession. A role in a Davidic kingdom given to a single person not a group. Jesus makes him alone the rock on which he built his church, and asks him alone to "tend his sheep".
Okay but now you're interpreting the scripture, right? And you know your interpretation of those passages is correct, how? I'm not saying it's wrong, I'm not saying it's right: I'm simply saying, you're in no better position to anyone else at this point. You're interpreting scripture just like every Protestant. You're engaging in "sola versea" right now, are you not?
So wherever Peter and his successor is, there is the true church.
Yet I see nothing concerning Jesus saying to Peter, "To you and all your successors I give the keys" so...
Orthodox has a similar problem all others do - it is the name for a group of denominations, (not a single denomination ) of many both autocephalous and autonomous churches that do not accept a primary authority, so do not agree with each other on some issues. Some accept some councils, others accept others eg Chalcedonian/non chalcedonian. All have made their own "popes" Some are larger than others.
Yet the schism is there, isn't it? There are many such churches, the schism of tradition isn't soley Catholic and Orthodox; it's greater than those two. And their tradition and doctrine provides similar interpretation of scripture to show that they are the true church. In the end, there is no recourse in citing tradition as some "sure authority" to the "true church" and every tradition-based church suffers from the same schismatic problem as protestantism. It seems to me that God in His wisdom has pulled the rug out from under the "sure tradition" tradition long ago.
The point is when you lose the source of ultimate authority, there is bound to be drift. Because orthodox did not lose tradition, or lose the teaching of early councils, it has not become as wayward as Luther and all the reformers that followed. But it cannot be the true church for the first reason given.
The authority of the Orthodox Church interprets the scripture differently than the Catholic Church, and so your "it cannot be the true church for the first reason given" is just an appeal to interpretation of scripture which may or may not be correct. You only think it is correct because your church beleives it so; the same reason Protestant sects believe their interpretation is correct while other Protestant churches are not.
The exegetical cart wheels used to deny the rock of the church was Peter would be laughable, were they not so serious. All hermeneutic rules are broken by those seeking to pretend it was "peters confession" or such errant nonsense, to avoid the obvious truth. Peter was the Rock!. God has chosen a variety of others in different eras to lead and represent his church on earth: for example Abraham was made "father" of the church given that name by God! Moses led - indeed we see that "moses seat" referred in the NT was a source of truth.
Okay but again you're engaging in the same interpretive exercise as any Protestant. I'm not saying, you can't interpret scripture; but that your practice is the same practice of every Protestant which causes "schisms", so you're in the exact same boat as they. You can't fall back to an appeal to tradition as some "final authority" when tradition itself is "schismatic": if the Catholic church was the one-and-only traditional church, then your argument would be reasonable; but it isn't and so it isn't.
And in taking "the book alone" you are taking the path that launched 10000 schisms.
I would reply that by taking "the book with tradition" you are taking the path that launched 1000 schisms out of the trailhead that launched 100 schisms. I'd also note that there's no support that "sola scriptura" is the actual cause of the schisms. By way of analogue, I talk to many Protestants and many times their interpretation will be schismatic to mine, and the cause of the schism isn't "sola scriptura" at all. The cause of the schism is that
they haven't even read the scripture in depth; they haven't studied it in depth. They have a cursory knowledge of a smattering of books and passages, based on what they have been taught listening to some "authority" in a pulpit who likewise has not studied the scripture in-depth but went to some cursory college based on tradition and so forth.
So when you blame "sola scriptura" for the schisms in the church, I dispute that and say, your proposition needs supporting evidence to be considered reasonable. It's reasonable to claim that schisms are being caused by plain, old-fashioned,
lack of study or "ignora scriptura"
Sola scriptura, is neither logical, biblical, historical or evidential. In short it is a reformation falsehood.
Things are easy to say; but support for claims is what makes a claim reasonable, instead of baseless opinion. I see no support for the above claim.