While it's good to become familiar with the specifics so that you can process the allegations correctly, it boils down to something very simple: the Israeli state and their Zionist backers gladly lie to justify every bit of violence they do to Palestinians. Accuracy does not matter to them, only consent for apartheid, occupation, genocide. When you contradict them in-person they become outraged and start hurling baseless accusations (e.g. antisemitism) for the simple reason that they have no basis other than ethnic supremacy and a desire to punch down, but they know they cannot actually say this.

Treat such people like you would Neo-Nazis. You will not convince them, they don't care about what is true or right, only the elevation of their own status. Instead, you must out-organize them. Join and build organizations that are coherently against the occupation and treat it as an ontological evil like apartheid in South Africa. Do not let yourself be coopted by the people supplying the weapons and diplomatic cover to carry out this racist project.