How do you graph using intercepts

How do you graph using x and y intercepts? Please be super detailed!!!
I am in Alegbra one as an 8th grader and I really need help.
Some examples from my book:
Graph each equation by using the x- and y-intercepts
y=(-3)-x
or
x+4y=10

Please go through step by step, if possible, help me with both problems. If you don't have that much time, please do the first one.

Again, I need a ton of details and please explain the steps and how you go the graph.

Thanks!

If you look at a graph, you will notice that the y axis goes straight across zero on the x axis. That means that where a line "intercepts" the y axis, x will be equal to zero.

In order to find the "y intercept" point, you take the equation for a line (since its representative of the line), and you substitute zero for x in the equation.

x + 4y = 10

Substitute zero for x

(0) + 4y = 10

Solve for the y coordinate

4y = 10

y = 10/4

y = 5/2

So when x is equal to zero, y will be equal to 5/2, making the y intercept (0, 5/2)

The same goes for the x intercept, because it's at y=0 on the graph. Substitute zero for y.

x + 4(0) = 10

x + 0 = 10

x = 10

So that line intercepts the x axis at (10, 0)

Notice how I'm getting the x and y coordinates? I'm substituting zero for one, solving for the other, then using zero and the number I got for the coordinates.

Next, you plot (0, 5/2) and (10, 0) on the graph. One will be on the x axis, and one will be on the y axis.

To finish, draw a line across those two points. It will be the line represented by x + 4y = 10.

----------------------

y = -3 - x

Substitute zero for x

y = -3 -(0)

Solve for y

y = -3

So you know that (0, -3) is the y intercept of the line.
Next, substitute zero for y.

(0) = -3 - x