I have read it cover to cover. It took a very long time, because it would put me to sleep, but I can not recall all details, just the ones that made an impression.
In Sunday school when I was 12, the class read the Bible cover to cover over a year long span.
Later, in high school I again read it cover to cover. The "begats" were difficult as I gave not one shit about the genealogy of ancient Hebrews. Other sections were entertaining. The New Testament is vastly more readable than the Old.