In Abraham Lincoln's own words, he went to school "by littles." He did have a small amount of formal education, but it probably didn't amount to more than a year in total. When Lincoln was six years old, he and his sister briefly attended a subscription school located a few miles from the family cabin in Kentucky, but the school was only open for a few months a year. After the family moved to Indiana, he again briefly attended school in 1819 when he was ten. He also attended itinerant schools known as "blab schools" where students learned the basics of reading and writing. As you can see, his formal schooling was so brief as to be negligible.
However, once Lincoln learned to read, he was a voracious reader and devoured any books he could borrow. Besides the Bible, he read books such as The Life and Memorial Actions of George Washington by Parson Weems, Pilgrim's Progress by John Bunyan, Robinson Crusoe by Daniel Defoe, and Aesop's Fables. He self educated himself in grammar, mathematics, and eventually enough law that he could pass the bar exam and become a lawyer.