This is the advice I'd give to my children:
Focus in understanding the meaning of the Cross. Live at the Cross, because what Jesus did for us is bigger than what we can imagine. Pursue the revelation that through Christ you are a son of God if you believe in Him, spend your whole life believing it; Pursue the revelation of God's love for you even when you don't understand it, even if what you read in the Bible doesn't make sense, even if you don't feel it, even if your circumstances tell you otherwise and even if most of the world is against you (even the church), never stop pursuing His love, and accept it. Always seek the Kingdom of Heaven first (seek to understand it) and its righteousness (what Jesus did for you) and everything else will fall into place.