Why does Microsoft Excel do this with graphs and how can I fix it?

I have data tables in Microsoft Excel (on mac). I’m trying to make a scatter graph with two of the columns in my table. I select the columns and select scatter graph from the options. Instead of giving me one of the columns on the y-axis and one of the columns on the x-axis of the graph and plotting one series of corresponding points, it gives me two data series (one for each column of data I suppose) and a stupid irrelevant scale on the x-axis. How do I fix it?

So for example instead of this, I get this.

HELP PLEASE I’m about to throw my computer out the window.