Think about EU finances. All of the below is from my general understanding and could well be wrong, so it should only be taken as a starting point for further research.
Income from the member states for each year is linked to the current size of their economies, and tariffs; the EU has no direct control on its income.
Expenditure each year is agreed by the member states in an annual budget.
The EU cannot run a budget deficit and cannot print its own currency(as far as I am aware), but the annual payments from member states are legal obligations i.e. The EU can sue the member states to get them paid.
On top of the annual cycle, there is a longer term (6 year?) cycle where multi-year infrastructure programmes are agreed. However payments on these long-term programmes are subject to the annual budget limits, and contributions from the member states where they are being carried out ( EU does not provide 100% funding). Therefore commitments under these longer term programmes are different in nature to the binding commitments in the annual budget. Using the same word in different context leads to confusion, but EU processes are confusing.