can you please explain exactly why all the eastern religions are false, and idolatrous, for jews? I agree that they are but am trying to figure out how to explain to someone else. thank you

Any concept of several gods is obviously a problem for monotheism, as is any kind of physical gods. In addition to being paganist, these religions had (today, they have all been influenced over time to accept morality, as does all of mankind) serious moral problems as well. See my article here on "Monotheism and Morality, Paganism and Immorality".