What is an equation of the line that passes through (-3,6)and is parallel to the line with the given equation: y=-x-5

Slope of line y=mx+b is m.

For L1: y=-x-5, slope, m = -1.

A line of given slope m passes through a point P1(x1,y1) has the equation as follows:
(y-y1)=m(x-x1)

The given point, P1(-3,6). Therefore the required line can be calculated.