You create an object with the new keyword. This allocates memory for the object and returns a reference to it:
Car myCar = new Car();
Car on the left side is the type. myCar is the variable that holds a reference to the object. new Car() calls the constructor and creates the object in memory.
If you skip new and write Car myCar; alone, myCar is null. Trying to use a null reference throws a NullPointerException at runtime. Always pair your variable declaration with new when you want a usable object.