Excel can be started in several ways depending upon the windows version you are using

You can have a Excel Icon in your task bar button

Starting Microsoft Excel in Windows 8 

In Windows 8 you can click on Windows Button like this

When you will click on windows button you will see group of programs and you will also see Excel Icon you can click to start

You can Also click on Search Button

and type Excel to start Excel

When you will click on Excel it will be started

Starting Microsoft Excel in Windows 10 

Click in Windows Icon on the bottom left

and start typing Excel and press enter like this

When you will press enter you will see following Screen

You can either Click in New or Blank Workbook and double click on it

Excel will be started and you will see screen like this

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