Newton's Method of Approximation

Use Newton's Method of Approximation to approximate the zero of the function in the indicated interval to six decimal places

$\displaystyle f(x)={x}^{3 }+3{x}^{ 2}-3 $ in the interval $\displaystyle [-2,0]$

I know how to use Newton's method of Approximation but what I am confused with is 2 things:

1. What number do I use in my approximation (i.e my $\displaystyle {x}_{0 }$ )

2. When it says to six decimal places does that mean I have to do the approximation six times?