+1 for the 3blue1brown recommendation. Between the two, a non-mathematician can acquire a layperson's comprehension of the Riemann Hypothesis. Additionally, John Derbyshire (of the unfortunate views regarding race) wrote a very good book "Prime Obsession: Bernhard Riemann and the Greatest Unsolved Problem in Mathematics" that covered both historical and mathematical aspects of the Riemann Hypothesis [0].

[0] https://www.amazon.com/Prime-Obsession-Bernhard-Greatest-Mat...