Oracle has a good set of tutorials for learning Java. There are also many books about Java. Are you brand new to programming, or do you already have some programming experience with other programming languages?
Though you may be tempted to jump into using an IDE, I recommend learning with the command line first. It will allow you to focus more on the language and not learning how to use the IDE. Above all else, please don't give up when it gets frustrating, and it WILL get frustrating. There is no harm in taking a break and regrouping to tackle a programming problem. Good luck with your new journey and don't forget that we are all resources for each other on here.