You need a proper PC or an Xbox One with a Gold subscription to grab a copy.
If you are among the lucky players that are Xbox Live Gold subscribers with an Xbox One available or you have a proper rig and a Steam account, starting from now you can download Fallout 4 and play it for free. The trial ends on May 28th.
The trial includes the core game with all base features including mod support. If you will like your experience, there’s a chance to get it for a discounted price, with quite nice offers for the season pass and the full package as well.