I am so confused with constructors, parameters and fields? Can anyone help me

The link to the section I need help is:

https://www.codecademy.com/paths/ap-computer-science-a/tracks/apcs-object-oriented-programming/modules/apcs-what-are-classes-objects-and-methods/lessons/java-introduction-to-classes/exercises/classes-assigning-values-to-instance-fields

What are you confused about? Im doing the Java course myself so I might be able to help?