I need to know how can an 8 year old girl become a famous singer? And I need all the steps.

She very likely cannot.

Has she had voice lessons and can she play an instrument or two and has she performed in public a lot?

Extremely unlikely as a singer.

Shirley Temple was the last child singer that ever achieved more than 15 minutes of fame. But eventually you will become an adult.. and you will have a lot of practice by then... so if you have the talent... and a boatload of luck... who knows.

You become a singer by singing. To become famous requires a lot of luck in addition to talent

There are no steps. If there were, everyone would be following those steps to become famous.

I do have to ask, what is an 8 year old doing on a Q & A site? I'm not very comfortable having a child this age on the site.