Hey, you can't convert an FME script to python.

You can add start/finish python scripts, call python scripts from the workbench (PythonCaller/PythonCreator, SystemCaller) and you can also use python to call a work bench (something like os.system())

When you run a workbench the first few lines of the Translation Log contain the command line parameters to run the job

So can I use the first few lines of the Translation Log to insert it in python and create a little app or not?

Yes, but the machine you run in on will need to have FME installed and licensed. Why are you needing to call fme from python?

I just need to remake the same transformation in python​

All that the first few lines are going to do is call FME to run the process. To recreate the logic in Python you're going to have to start from scratch. If you're dealing with any spatial operations your going o have to use libraries such as ArcPy (Requires Esri License) or GDAL