Answer:
See below (along with attached graph)
5th point can be of personal choice
Step-by-step explanation:
X-intercepts/Roots
[tex]y=-x^2-2x+3\\\\0=-x^2-2x+3\\\\0=-(x^2+2x-3)\\\\0=-(x+3)(x-1)\\\\x=-3,\: x=1\\\\(-3,0)\:and\:(1,0)[/tex]
Y-intercept
[tex]y=-x^2-2x+3\\\\y=-(0)^2-2(0)+3\\\\y=3\\\\(0,3)[/tex]
Vertex
[tex]x=-\frac{b}{2a}\\ \\x=-\frac{(-2)}{2(-1)}\\ \\x=\frac{2}{-2}\\ \\x=-1\\\\y=-x^2-2x+3\\\\y=-(-1)^2-2(-1)+3\\\\y=-1+2+3\\\\y=4\\\\(-1,4)[/tex]