While Morse code is not required to get your license, it is a popular mode and a lot of fun!
You can learn a bit about the history of Morse Code, the development of the telegraph and its impact on communication. (thanks to Payton Conway for this link to a great site!)
https://www.emissary.ai/telegraph-morse-code-text/
You can find a lot of study aids online or you can purchase a system. There are apps aplenty, but there is no one fool proof way to learn "the code" And you must committ to whatever you choose.
https://www.cq2k.com/index.html
http://www.arrl.org/shop/Your-Introduction-to-Morse-Code-audio-CDs
https://www.w5yi.org/catalog.php?sort=17
http://www.hamwhisperer.com/p/morse-code-course.html
The ARRL maintains an code practice schedule - it changes occaisionally so we have provided a link below
http://www.arrl.org/code-practice-qst-source
They also offer some code practice files to listen to