The short version people give — "two versions of the same ending" — undersells how much is actually different content, not just tone. Let me lay out what's actually new in the movie versus the TV finale.
What's only in End of Evangelion: the JSSDF assault on NERV headquarters, ordered by SEELE to seize the Evas by force, is a whole extended sequence that doesn't exist in the TV cut at all — it's some of the most brutal material in the franchise. Asuka gets one last fight in Unit-02 against the Mass-Produced Evangelions before that ends the way it ends, which is a scene the TV episodes never touch. Kaworu, who's central to the TV finale's most tender moment, barely appears in the movie by comparison — the emotional center of gravity shifts to Asuka and Misato instead.
What episodes 25–26 do instead: they stay almost entirely inside Shinji's head — abstract, minimal animation, therapy-session structure, working through his self-worth issues directly with the audience rather than showing an external event. It reads more like a clip show crossed with a psychological breakdown than a conventional finale, and that's on purpose as much as it is a product of the production running out of time and money to animate a "normal" ending.
The endings do land in roughly the same emotional place — Shinji choosing to accept his own existence, said either as "I can stay here" or, on the beach with Asuka, something much colder and more ambiguous. So no, they're not contradictory, but I'd push back a little on calling it just two camera angles on one event — the movie tells you what physically happened while the world was ending, and the show tells you what was happening inside Shinji instead. Both true, both needed if you want the full picture.
As for Rebuild: it starts as a fairly faithful retelling in 1.0 (2007), splits off hard by 2.0 (2009), and by 3.0 (2012) it's telling a genuinely different story with the same character names. 3.0+1.0 (2021) is the actual ending of that continuity. I'd watch the original series and End of Evangelion first regardless — Rebuild leans on you already knowing that version to land some of its choices.