If you’re not familiar with resonance, it’s a super important component of a voice (possibly even more important than pitch), which is determined by the distance from your mouth to your voice box. This video gives examples of each combination of high-low pitch and bright-dark resonance, the most important to know is “low-pitch, bright-resonance,” if you know Stephen Universe, Peridot’s voice is my go-to example, generally, people describe that sort of voice as “nasally” or “annoying” but notably, even if it sounds bad it still sounds female. The reason it’s important is that if you break down each component of voice and work on them individually, you can get better results than if you try to do everything at once. My strategy is to aim for a “Peridot” voice first, and then raise pitch from there, which is easier/more natural to do.

To get brighter resonance, you need to learn how to control the muscles that raise/lower your voice box, and there are two exercises that help with that. One is called, “swallow and hold” - put your finger on your voice box and swallow and you’ll notice it raise, try to “hold” for a bit to keep it there, then gradually release muscles, taking note of when the voice box lowers. The second is “big dog, little dog” - pant like a dog and switch between imitating a big dog and a little dog, while again keeping a finger on your voice box to note its movement. When you pant like a little dog, it should raise higher, again, pay attention to which muscles you’re using to move it. I believe both of those exercises come from the channel I linked before but I don’t remember which specific video.