Futura is a commercial font owned by Linotype corporation
You would have to buy the font, unless you can find a similar free type font.
Unfortunately commercial fonts are extremely expensive to buy. A single face (say Futura Black) could set you back something like $40. A complete family like all the Futuras would be in the $100s.
While companies like Linotype need to earn a buck, their business model. IMO, is still in the 1990s, when they were selling font collections to big publishing companies.
In the modern age where you can download albums from iTunes, Movies from the Internet and apps from various app stores, I think it is high time that font companies adapt their model to people who want to legally buy Fonts without spending more than the cost of an iPad.
Sorry for the rant, but fonts are expensive - but I think that the companies would sell more if the average user could buy them at affordable prices.