No spell will make you famous, they may assist in good luck or good fortune for interviews or during performances, but you will need mundane practice to make you good at singing.
Maybe look into singing lessons, but it's good to remember that life is not all about being famous, it's about doing what you enjoy, if you enjoy singing, do it for the joy of it, not for the pursuit of fame.
In history the most significant and famous (or infamous as well, I guess) people are those who had a consuming passion for what they do, and that is what lets them work hard enough to excel at what they do enough to become known for it.
For example it isn't just a singer's skill in their voice that makes them a rock star. Hundreds of people have amazing voices but they don't put that voice to use. it is also the artists willingness to constantly work at that voice. To take the risk of leaving safer jobs or home life to seek a living as an artist. Working at creating new songs, and performing them in a way that others will feel drawn to. Working to get themselves known and promoted. And so on.
Another option would be to build a spell or two for inspiration, confidence in the self, and finding your Labor of love. IE; the activity that most synchronizes to your nature, ideals, and passions. In finding that, you might gain a measure of the drive and intensity that will allow you to find fame as well.
The critical goal would be finding that labour of love. If you don't have a passion for what you want to do, then you won't want to do it even if you are good at it. Especially during the difficult times and challenging tasks that underlies the glitz and glamour of fame.