Answer
Slope: $3$
$y$-intercept: $1$
Work Step by Step
The slope-intercept form of a linear equation of a non vertical line is $y=mx+b$, where $m$ is the slope and $b$ is the $y$-intercept.
We use this to pick out the slope and the $y$-intercept from the equation $y=3x+1$.
Since $3$ takes the place of $m$ in the equation, it is the slope.
Since $1$ takes the place of $b$ in the equation, it is the $y$-intercept.