How do I create an oval shape

Completely new: how do I create and oval shape i. 2d?

Make a circle
Use Ctrl and Scale

Learn the basics: https://learn.sketchup.com/track/sketchup-fundamentals-part-1

Additionally, I always draw two sets of guides, one set for each axes X and Y such that you end up with a rectangle representing the extents of the oval.
Set 2 center line guides one in each direction, draw a circle centered on the intersection of the two centerlines and scale the circle using the Ctrl modifier key until the oval fills the rectangle.

Guides are an unnecessary step. Follow @mihai.s gif.

Start a circle, type your desired dimension, (radius). Start Center Scale the circle in one axis, type second dimension (diameter). Done.

Thanks for that explanation. I prefer graphic solutions for my little brain.

Strictly speaking, a scaled circle is an ellipse, not an oval, but that’s probably what you wanted anyway. An oval is made with two different pairs of pie slices butted together.

Make a circle > Draw the diameter with a line > Scale half of the circle (erase the diameter line)

Thanks, @RTCool!

Actually, I was thinking more in these terms:

Very similar but not exactly the same shape that have different methods of construction. When it comes to making things on an construction site, the oval is a be easier to construct, and lends itself better to parallel offsets like making a roadway, but it’s not quite the same thing as an ellipse. In SketchUp and other programs, it’s the ellipse that’s easier to make.

Now, there are several options to create that oval, depending on the desired shape

Thanks for the examples, RTCool!