It would not hurt to try. Using your phone to record your singing may not be the best idea, the microphone is so small that singing even with normal volume gets the recording easily distorted.

USB-connected microphones are pretty cheap and will perform much better, just hook one to a laptop and use any simple recording software.

And I recommend starting small with children’s songs. “Twinkle Twinkle Little Star” with it’s straightforward ascending and descending melody is a great starter, or at least for me it was.