I believe that we lived before this incarnated mortal life, that we each had a premortal life as a spirit.
I am not, however, clear about the details of this life; but there are important general implications if we knew many things before this life, things we did not learn from experience, things that may include divine intentions and plans for human life on earth.
Foreknowledge of such things might well include what would usually be regarded as prophecy.
Perhaps most importantly, because of premortal experience, it follows that everybody would be in a position to know about Jesus, to know what Jesus did; and even to know and recognize Jesus.
If this is the case, then it makes easy sense of the requirement that all Men need to 'follow' Jesus in order to attain eternal resurrected life.
If it was supposed that we need to learn about Jesus during our mortal lives - this sounds an unreasonable requirement; because people might not have correct information about Jesus - indeed they might have no information at all.
Yet if everybody already-knows about Jesus, and would recognize Jesus if they met him; then the requirement to know and follow him if we want eternal life becomes a simple choice.