Hmmm, if you are new to Java I think this should be in the beginners forum.
Anyway, you can solve your problem by creating one class of your own, and using another class from the library that comes with Java.
First, create a class that represents one of the items you want to store. For example, if you want to store data about people, create a class that represents a single person and all their attributes (name, age, etc).
Then you need to create many instances of your class and store them somewhere together. The Java library provides different classes to help you do this, delete items, search for items, and more. Start with the ArrayList class.
I've tried to give you some general pointers. I hope this helps. If you need any more specific help, of course feel free to ask.