The question is about the difference between “The Episcopal Church” and “The Anglican Church in North America,” both churches in the Anglican Tradition in North America. Let me start by explaining a bit about Anglicanism.
Anglicanism has its roots in the 1900 year history of Christianity in the British Isles. Today there are approximately 80 million Anglicans worldwide. Anglicans see themselves as one expression of God’s One, Holy, Catholic (meaning"universal") and Apostolic Church and is characterized by an emphasis on liturgical and sacramental worship, Protestant beliefs and a love of the great traditions of the Church. Anglicans are bound together by a “common worship,” which is expressed and propagated in the “Book of Common Prayer” first drafted in 1549 during the Protestant Reformation in England. Anglican churches are also largely bound together ecclesiastically (organizationally) in what is known as the worldwide "Anglican Communion."
The Episcopal Church was formed after the American Revolution as an ongoing expression of Anglicanism in the United States. In recent decades, however, the Episcopal Church has progressively taken on a revised view of Anglicanism and of the Apostolic Faith, what is known as Modernism and Modernist Theology. The Episcopal Church today, particularly among its clergy, understands the Faith in some ways inconsistently with the Faith of the Apostles as recorded in Scripture and the Faith of much of the rest of the Anglican Communion throughout the world.
Two salient issues differentiating Apostolic Christianity (classic Anglicanism) from Modernism (The Episcopal Church) are understandings of the authority of Scripture and the uniqueness Christ. This is far too limited a venue to fully explain, but in modernist thought the revelation of God in Scripture in many of its facets is seen as outdated and overridden by modern experience and human intellect. Similarly, the uniqueness of what God has done in Christ has given way to an openness and inclusivity that trumps the apostolic understanding and eyeswitness experience of the uniqueness of the person and work of Jesus.