How will I know what my baby wants and needs?

It can be pretty daunting trying to figure out a newborn's wants and needs since there's no way for your baby to tell you anything. But don't fret, newborn usually cries if they're hungry or needs a diaper change like Diana mentioned or if he's uncomfortable (too warm), wants a cuddle or too tired. Learn to recognize cues e.g. rubbing of eyes and faces are usually signs that baby is sleepy so put him to sleep before he starts fussing too much. Don't worry about not being able to catch on his cues, as Heena mentioned, as you spend time with your baby more often, you'll be a pro at recognizing his different cries. Before I used to panic at the slightest cry bcos I wasn't sure of what my son wanted but now, I can easily remain calm and attend to whatever he needs quite promptly.