Particle Reach X

Consider a particle that performs a random walk on the integers starting at position $0$. At each step, the particle moves from position $i$ to position $i+1$ with probability $p$, while it moves from position $i$ to $i-1$ with probability $1-p$. If $p = 3/4$ and $k = 6$, find the variance of the number of steps until the particle reaches position $k > 1$.