CAN YOU GET WORLDBOX ON PC FOR FREE?

No, you cannot get WorldBox on PC for free. 

Beware of websites promising you the game for free, as they can be filled with viruses or deceiving software. 

You can buy the game on Steam directly. The developers don't approve of any other 3rd party websites, except Humble Bundle for early buyers. 

Better not risk your PC by using shady websites. Also be wary of illegal file hosting websites, as using them can be illegal in many jurisdictions. Better safe than sorry.