I am new to desktop apps. I have been reading guides, tutorials, and documentation but don't understand: 1 How do you define an install directory? The application I want to build will be managing file co tent in subdirectories, of the install directory. 2 Which gradle task makes the .exe? 3) when installing intellij there is a gui with options. Is something like that part of the application code or a separate application? If it is a separate application, how do you connect the selected parameters to the application installer?

You should first have a closer look at some of the provided examples to gain some practice. There is also a misconception in you questions. You ask “How do you define an install directory? The application I want to build will be managing file co(n)tent in subdirectories, of the install directory.” The install directory is normally defined by the defaults of the platform you install your software on but in general you do not manage any file content there. Simply because a regular user does not have write access to that place.

I needed to know the location to store files and found a nice little KMP library to do the job - Kotlin-Multiplatform-AppDirs