I have the .exe installation file for Firefox and I want to create a portable version for it as in my laptop any external software installed in C drive does not run.
How can I create a portable version of Firefox from this exe file?
you can download Mozilla Firefox, Portable Edition and then use MozBackup to backup your current Firefox profile (if needed) from installed Firefox on your C drive and transfer it to your Portable Firefox. :-)
Used this approach some years ago and worked very well. Result is fully working Firefox portable with all your settings, bookmarks etc. from your old installation.
For Linux, I created a download script here: https://gist.github.com/rubo77/b999c1bc6d10ab802536