First, click on the File tab.
Click on options.
You will get the "Excel Options" box. Select the Add-Ins.
Once you select the Add-Ins, You will see "Analysis ToolPak" under Inactive Application Add-ins. Select it and click on "Go" button below.
Once you click on the "Go" button you will get below box. Check "Analysis ToolPak" and click on "OK" button
Now you can find "Data Analysis" command under "Data" tab.
So now you can do data analysis like Regression, Fourier Analysis etc. using this Data Analysis command.