How to find Gradient and y intercept

Gradient:

Find two points on the line and with those two points, calculate the difference in height(y coordinates) divided by the difference in width(x coordinates). If you get a positive value, then your line will be uphill.

Y-intercept:

Use y=mx+b
Find the slope first using the slope formula which is y2-y1 OVER x2-x1. Once you have that, take a point from the line and substitute the x and y coordinates along with the slope into y=mx+b.

So if your slope was 2/1 and your point was (4,8), it would be:

8=2(4)+b
8=6+b
*subtract 6 from both sides*
b=2

I’m confused as to what you are asking 66 2/3 percentage wise