So, I really enjoy kind of whispering along with songs, and I've tried singing along with Nothing Else Matters by Metallica, and I came to the following conclusion:

A. I have no vocal range whatsoever, just like when I speak, it sounds monotone

B. I really don't know how to sing

Can someone help me?
You have to practice. You won't know how to sing right from the start, especially if you never really sang in your life. It takes time. Any the fastest way is to get a vocal teacher.
Joža je kul. On ma sirove z dodatki pa hambije.
Did you pick up the guitar and play Nothing Else Matters your first time seeing one?