There's been a major economic and political crisis in Venezuela since 2014 (actually, for years longer) that has turned into a massive constitutional crisis. So much so that to describe the problems overall would take a team of economists and foreign policy experts writing a book for publication by a university press.
Since I'm not fully qualified, I'm just gonna boil this down to the simplest explanation I can:
A dictatorial government over-reliant on a single industry (oil) is consuming itself in a wave of corrupt self-serving habits that fail to give the majority of the citizenry the fundamental resources (affordable food and housing) needed to live.
And because the people in power cannot admit to failure or allow others who can resolve these problems to enter into power, the only possible response by the majority of the people is to rise up.
At some point, and horrifyingly soon, Venezuela is going to explode in mass violence between the angry mobs and the heavily-armed military.
This won't be pretty.