cannot set up IDE

archive type not supported message when trying to open arduino-1.8.5-linux64.tar(2)

Change the filename to arduino-1.8.5-linux64.tar.

Evidently you downloaded it twice and the (2) was added to differentiate the two files.

Thanks! That worked and i opened install.sh and it just showed the code , it didn't run. As you can tell i'm new to this.

Are you using Linux?

open Terminal window
go the directory where the program was unzipped
type ./install and hit Enter key

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