Explain this quote in terms of Marx's view on history and society: "The Weapons with which the bourgeoisie felled feudalism to the ground are now turned against the Bourgeoisie itself."

Marx has a fundamentally progressive, one might say "evolutionary", view of history. He traced historical development through various stages—primitive socialism, slavery, feudalism, capitalism and finally modern socialism. His idea of historical materialism argued that history was shaped by material conditions, and that the battle to improve those conditions for the largest number of people represented the basic progressive thrust of historical development.
Marx's quote, "The weapons with which the bourgeoisie felled feudalism to the ground are now turned against the bourgeoisie itself" is from The Communist Manifesto (1848) and it's not difficult to understand what he means by the reference. The French Revolution (1789) was a bourgeois revolution, and represented a middle-classes attempt to challenge and overthrow the Ancien Régime, the monarchy and last vestiges of feudal privilege that remained in France in the late 18th century. The Revolution was largely successful in this objective.
By 1848 things had changed. The mass revolutions of 1848 in Europe were more than just bourgeois revolution, and to some degree represented the proleteriat, or working-class. Marx's quote captures this change, and he is suggesting that the writing is on the wall. He means to say that revolt and revolutionary action will eventually overthrow the power of capitalism too, leading to a socialist state. This is finally realized in one form as a result of the Russian Revolution of 1917.
https://www.marxists.org/archive/marx/works/1848/communist-manifesto/ch01.htm