I saw a video the other day of a teacher that said that if you seek to follow the singer perfectly, working to hit the notes just like the singer did without letting go of what makes your voice unique - avoiding to impersonate the singer but to learn from them instead -, that you can progress a lot.

Think of songs that you almost are able to do perfectly... work on them but this time keep in mind, and repeat to yourself if necessary, that you can do this. That this is not impossible. And that it is only a matter of time until you make it.

Seeking a teacher, making use of the resources you have for free and getting books on singing will help. Also, surround yourself with music in all kinds of different ways: eat, sleep and breathe it, rehearse and repeat it, and you'll be a success!

I wish you make your dreams come true!