RT @Rainmaker1973
Richard Feynman's Lectures on Physics are timeless: their main strength is in demonstrating how to reason about physics. You may not know all the lectures are completely online:

Volume 1: https://feynmanlectures.caltech.edu/I_toc.html
Volume 2: https://feynmanlectures.caltech.edu/II_toc.html
Volume 3: https://feynmanlectures.caltech.edu/III_toc.html