You need two circles, one larger than the other, with different fill colors.

You can drag out an ellipse holding the Ctrl key to make it a circle. Note that the height and width have to be equal for it to be a circle.

Note the width of the larger circle, Let it be X

Let the width of the smaller circle be Y

Fit the canvas to the width of the larger circle.

Now, the position of the Left of larger circle is 0, and the right of it (Left+Width=0+width) is equal to its width.

Calculate position of left of smaller circle as follows:

Left [Smaller]=X/2 -Y/2

Top[Smaller]=Left

If you need to position text at the exact centre of the smaller circle, you’d do it like this:

Left of Text=Left of smaller circle+Width of Smaller circle/2 – Width of Text/2

Height of Text=Top of Smaller circle+Height of smaller circle/2 – Height of Text/2