Read David L. Jones’ article about light high singing, very important information!!!
Some singers use the whistle register or falsetto to reach the highest regions. Singers like Mariah Carey and Minnie Riperton use the whistle register. Falsetto is commonly used by male singers, both in popular and in classical music. Andreas Scholl is a great example.
Many singers will experience some sort of fear to sing the high notes. Especially when you are exploring your highest regions, our body will need some time to learn how to stay relaxed while singing higher notes. So relax and give it some time!
You should always keep in mind that every voice has its limits when it comes to vocal range. So don’t push yourself beyond the impossible!
A voice teacher can help you to explore your voice and determine whether you can sing higher notes or not.