Hi, I am Dave, I will help you with this.
If F7 is the key for the keyboard backlight, and it is not working, try pressing Fn + F7, does that get the backlight working?
If it does, try pressing Fn + Esc to turn off the Function Lock so you can use F7 on its own again.
If that does not solve this, click your Start Button, then just type msinfo and press Enter, please provide a screenshot of the resulting System Information window.