You can manipulate charts in your document to make them look just the way you want.
Click anywhere in the chart to select it, then drag the chart to where you want it on the page (don’t drag the selection handles).
As you drag, yellow alignment guides help you position the chart in relation to other objects on the page.
If you don’t see the alignment guides, you can turn them on. Choose Pages > Preferences (from the Pages menu at the top of your screen). Click Rulers, then select the guides you want to appear.
Select the chart, then click the Arrange tab at the top of the sidebar on the right.
If you don’t see the sidebar, or it doesn’t have an Arrange tab, click 
in the toolbar.
Type values in the Width and Height fields in the Size section, or click the arrows next to the fields to set specific dimensions.
You can also select the chart, then drag any of the selection handles (the white squares) on the chart’s border to make the chart larger or smaller.
You can rotate a 3D chart to adjust its angle and orientation.
Click the 3D chart.
Drag the rotation control 
on the chart to rotate the chart until it’s in the orientation you want.