Life is extremely easy for most people in so-called civilised countries in our age. I doubt very much you've been tested. A few generations ago in the U.S. and Europe people knew war, political upheaval, poverty on a grand scale...I never heard of any of those people saying they knew all there was to know.
Truth is there is more to know each hour, and I, for one, find it difficult to study a tenth part of what I would be interested in knowing.
History and Fiction are two available sources where you will find reasons to reflect on whether or not you have experienced a small part of what is possible. Do you have a firm knowledge of history? human biology? mathematics?
Have you read the memoirs of any truly great individuals? Can you figure out how Julius Caesar was capable of subduing the Gauls? How Churchill could know in 1930 the events of 1936-45?
Are you still with the best person you've known in your lifetime?
Have you ever stripped yourself of all your relationships and made your way in a new location?
You sound fortunate, but I am sure there is a lot more out there.