Being nihilistic I would say Orthodox/Catholic church and Buddhism are not so incredibly different. Buddhism evolved from Hinduisism but removed caste system but it doesn’t emphasize that. In a similar way as Christianity is based on Judaism and doesn’t emphasize that either. There is similar approach and similar preoccupation with death. Monks mediate on decomposed bodies. There is a Christian believe in t death and possibility of going to hell.where you will suffer..There is a Buddhist hell where you will equally suffer.There is the same devil (mara) There are Hindu Gods in both Hinduism and Buddhism .But in Hindu Heaven they suffer because they do exist. Christian God is the same as in Judaism.
In Buddhism you meditate. In Christianity you pray or say litanys to Holy Mary. Whether you go to Christian paradise or get rebirth in Buddhism is not so much different. There is an assumption in both religions that you will get blissful transition. But there is a conflict in Buddhism because first you try to remove your ego and in the end you get Rebirth (Recarnation exists only in Hinduism) of the same personal identity.