You can practice falsetto by learning to sing bel canto.

By singing the bel canto word "Ah" in a transitional stage from the lowest pitch to the highest pitch, the entire body's energy is driven by even Qi throughout the body. Starting from the lowest voice, you can find a perfect singing point by practicing between the back nasal sounds. You can find the correct singing method of falsetto by using the back nasal sounds and starting to hum slowly.

Extended information:

The so-called "false voice" refers to the sound produced by consciously controlling only part of the vocal cords to vibrate during singing. This sound is better than the sound produced by the entire vocal cords. The "real sound" that all vibrates is either high or weak, and has a special timbre.

If the falsetto is not used properly, there will be a lack of breath, excessive trembling, etc. The falsetto still needs a long period of training to be perfect. Most people can choose to train with the real voice to make progress. The speed will speed up a lot, and if the high pitch is purely falsetto, it will look lackluster.

Most pop singers sing in their real voices to achieve a natural, friendly, and colloquial style. Some female singers mainly use falsetto when singing songs with a wider range and stronger artistic quality.

Reference materials:

False voice_Baidu Encyclopedia