When you take someone or a company to court and sue them and then you win that lawsuit then the judge orders that the person or company pays you the money owed after the lawsuit.
Then you have to give the person or company some time to willingly pay out the money owed to you after the lawsuit and then if the person or company never pays out after a certain time then you go to the sheriffs office with your paperwork about the lawsuit and then the sheriff can force the person or company to pay you.
The persons or companies bank can be levied, liens can be put on their house or other property etc and even wage garnishments.
You need the proof from the judge though that you have the right to collect before they'll do anything to force the person or company to pay you.