I would like to create apps, among other things.. I hear that Java is what need? Someone suggested Scala.
What kind of apps? Android? iOS? Web? Enterprise?
Java is what you need for android (and enterprise) but the principles you learn with Java will apply to lots of other languages.
Scala is a "functional language" based on the same "foundation" as Java but I would not recommend you starting with a functional language bc in general it's harder to wrap your head around some that style unless you have a very high level math background.
As mentioned above, the best way to learn would be to have a project and goal in mind and then figure out what you need to know and just learn and build at the same time