I had a quick look at the site and got to the end of the 13 first points it makes. Of them, point 1 is so unspecific as to be almost meaningless. Point 8 is basically false. Point 9 deals with an outward form of worship, not an essential of either catholic or orthodox dogma. The first half of the first sentence of point 10 is false so I didn’t worry too much about the rest.
Yes, there are differences between the Catholic and Orthodox traditions and beliefs. But perhaps this site isn’t the best place to learn about them. Too many things are false or badly researched and seem to arise from a complete lack of understanding of “infallibility”. If only everyone could be properly educated in what catholicism really teaches and practices many, but by no means all, of the arguments would fade away into nothingness.
In a few moments of browsing I found this. It looks good. If you want to understand the issues try this one:
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