Complex sentence: Vanyel Ashkevron, age sixteen, is the heir to a great estate, "Forst Reach", though he does not measure up to what his father, Lord Withen, deems to be a "proper" man.
Split into simpler sentences: Vanyel Ashkevron, aged sixteen, is the heir to a great estate, "Forst Reach". However he doesn't measure up to what his father Lord Withen deems to be a "proper" man.