It's takes years to learn truths. First ask yourself if you are clear on what you know. Be open minded , search and research it..
The reason there are so many churches is because people feel they have the Truth and others don't.
I don't think people teach false doctrines on purpose but because they themselves don't know have truth.
In Matthew 22.29, Jesus answered a question by saying to the people, You err because you do not know the scriptures or the power of God. People are taught so many different things and they believe them because they do not know the Bible and what the Bible teaches.
Anyway..write hubs on what you know and use the forums,
that way you're not pointing your finger at anyone.
There are people who will never understand.