Your code can
request full-screen display using the fullscreen API:
Fullscreen API - Web APIs | MDN[
^]
The user/browser is free to block the request. And the user can always exit full-screen by pressing the
Esc key.
However, Javascript running in a web page
cannot launch applications on the local computer. The closest you can get is to link to a file which would normally open in the desired application. However, the user is free to save that file instead of opening it, or to cancel the download.
And before you ask, this is a security feature. There is no way for your code to work around it.