Islam teaches about Judaism and Christianity
It teaches that Jesus is the only way to the father? Exactly what does it "teach" about Christianity?
You are starting to condescend. That would be similar to mockery, which is not favored by Jesus nor God.
Believing that Jesus is the only way to the father is identical to believing that Mohammad's advice is the only way to heaven. It's like saying: "Don't worry about the details now, but read up on them later. For now, just make the dugards and signs that confirm you to be one of
us."
If you want to know what the Koran teaches about Christianity, then buy a decent translation of the Koran, and look up "Christian" and "Christianity" in the index. Do not look up "infidel" as that refers to the moon worshippers that persecuted Mohammad for preaching about Judaism and Christianity, for whom he had no patience.
You tell me how Coptic Christianity differs from the Catholic and Orthodox flavors and why, if you are able.