His Wikipedia entry is of sufficient length to provide a reasonable sense of his life and career. Some of the paintings shown below are discussed, along with two of his early, largely representational paintings.
Boccioni was serving in the Italian army when he died as the result of an accident. As the Wikipedia entry notes, this was when he seemed to be drifting away from Futurism. From the images shown there, it seems he was beginning to experiment with styles being used in Paris. How he might have developed had he survived the Great War is unknowable, of course.
This painting is partly shown at the left of the photo above.
An early Futurist painting by Boccioni.
The Wikipedia entry has this dated 1915 and cited as a sign that Boccioni was drifting from Futurism. However, most items relating to this work found via Google have its date as 1912. This seems to make sense because this is clearly a Cubist-style portrait similar to what Picasso and some others were painting around that time. Boccioni must have been experimenting here.
An important element of Futurist painting was attempting to depict motion.
Futurism was in favor of warfare.