Hi and welcome.
I think you are talking about this file
Unzip the file. (remember where you unzip to)
Inside you will find a folder called TB30_Episilon
Put that folder inside the /Simobjects/Airplanes in FSX
You will find your aircraft under 'EADS Socata'
You can see this little tute as another examplehttps://simviation.com/1/fsxinstall
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