Creating a chart with three axes can be a bit tricky, but it is definitely possible in Microsoft Excel. Here's how you can do it:

1. First, select the data that you want to use for your chart. Make sure that you have all the data that you need for each separate series of data.
2. Next, click on the Insert tab in the ribbon at the top of the Excel window. Then, click on the Recommended Charts button to see a list of chart types that Excel recommends for your data.
3. Scroll down until you see the All Charts tab, and then click on it. From there, you should see a list of all the available chart types in Excel.
4. Look for the chart type called "Combo". This is the chart type that allows you to create a chart with multiple axes.
5. Select the "Combo" chart type, and then click on the OK button to create a new chart.
6. In the "Combo Chart" dialog box that appears, you'll see a list of all the available chart types that you can use for your chart. For each series of data that you want to add to the chart, select the chart type that you want to use from the drop-down menu.
7. Once you've selected the chart type for each series of data, you can then customize the chart by adding titles, labels, and other formatting options.
8. To add a third axis to the chart, click on one of the series of data in the chart. Then, right-click and select "Format Data Series" from the context menu.
9. In the "Format Data Series" dialog box, you'll see a section called "Series Options". Under this section, you should see an option called "Plot Series On". Click on the drop-down menu next to this option, and then select "Secondary Axis".
10. Repeat this process for each series of data that you want to add to the third axis.

That's it! You should now have a chart with three axes, with each separate series of data plotted on its own axis.