A: Yes. The 2007 novel stands alone. However, you will miss the cosmic context of Morgoth’s curse. The book includes a helpful introduction.
If you finish The Children of Húrin and want more, look for The Fall of Gondolin (2018) and Beren and Lúthien (2017), also edited by Christopher Tolkien. And yes, legal PDFs exist for those too—if you know where to buy. J.R.R. Tolkien - The Children of Hurin -PDF-