It is well known that using the weight lattice of type $E_6$, $P$, and the lattice construction for vertex operator algebras one can obtain all three level 1 irreducible $\tilde{ g}$-modules with $V_P = V^{ \Lamba_0} \oplus V^{ \Lamba_1} \oplus V^{ \Lamba_6}$. The Dynkin diagram of type $E_6$ has an order 2 automorphism, $\tau$, which can be lifted to $\tilde{ { \tau}}$, a Lie algebra automorphism of $\tilde{ g}$ of type $E_6^(1)$. The fixed points of $\tilde{ { \tau}}$ are a subalgebra $\tilde{ a}$ of type $F_4^(1)$. The automorphism $\tau$ lifts further to $\hat{ { \tau}}$ a vertex operator algebra automorphism of $V_P$. We investigate the branching rules, how these three modules for the affine Lie algebra $\tilde{ g}$ decompose as a direct sum of irreducible $\tilde{ a}$-modules. To complete the decomposition we use the Godard-Kent-Olive coset construction which gives a $c = \frac{ 4}{ 5}$ module for the Virasoro algebra on $V_P$ which commutes with $\tilde{ a}$. We use the irreducible modules for this coset Virasoro to give the space of highest weight vectors for $\tilde{ a}$ in each $V^{ \Lamba_i}$. The character theory related to this decomposition is examined and we make a connection to one of the famous Ramanujan identities. This dissertation constructs coset Virasoro operators $Y(\omg,z)$ by explicitly determining the generator $\omg$. We also give the explicit highest weight vectors for each $Vir \otimes F_4^(1)$-module in the decomposition of each $V^{ \Lamba_i}$. This explicit work on determining highest weight vectors gives some insight into the relationship to the Zamolodchikov $W_3$-algebra.
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