PowerPoint comes with an extensive set of ready-made shapes that you can use to easily draw shapes on your slides. The Shapes gallery contains more than a hundred common shapes and lines, such as stars, arrows, and speech balloons.
There are a few different ways to modify the shapes in a presentation. You can drag them to a new location on the slide, resize them, or use the adjustment handle to change the shape’s most prominent feature.
If you decide that you’d like to use a different shape instead of the one that you’ve already added and formatted, you can switch it out. This can be really helpful if the shape already has effects or styles applied to it because they'll be applied to the new shape.