You'll need to do a little research for this.

If it doesn't work you'll probably just get an error message. If you're trying to autostart some other program you might only need to substitute that program's name and options for the ones I used here. I described how I set up Qjoypad so I could use an inexpensive gamepad to control one of my Pi projects here. This should work with most (if not all) programs on your Pi, but for this Instructable I'm using two examples from a recent project of mine: the Chromium browser and Qjoypad.

There is a lot you can do through your desktop though without ever facing the command line in a terminal. (Welcome to Linux!) While understanding the command line is a foundation skill if you're going to get serious about understanding how your computer works (and making it do what you want it to do) it can be a little intimidating and a lot confusing to new users. Most tutorials for autostarting programs will direct you to use commands in a terminal window and edit files you've never heard of.

Autorun program