Can I upgrade Windows XP to Windows 7?

No, not directly.

Windows XP cannot be upgarded to Windows 7. It has to be done as a clean installation. This means wiping off Windows XP then starting a clean installation of Windows 7.

Create your installation DVD/USB  then restart the computer and boot from the DVD or USB.

During the installation choose CUSTOM (if you choose upgrade it will not work).

Keep in mind that with a clean installation you will lose all files from your hard drive, so be sure to backup any files you wish to keep.