1. You can access the drawing shapes by clicking on the 'Insert' tab then on the drop-down under 'Shapes'
2. You can save one click by adding the drawing shapes to the Quick Access Toolbar as follows..
Click on the Insert tab now right click on the large 'Shapes' icon and choose 'Add to Quick Access Toolbar'
You should now have an extra icon on your Quick Access Toolbar from which you can choose a shape.
You asked about getting the drawing tools to show on the ribbon. I don't believe you can, and in any case I couldn't imagine that adding about 180 drawing shapes to the ribbon would really be very good?