>>89762050You need to actually, unironically, literally just start recording yourself saying lines and listening to them. Imagine you are your character and LARP in full, imagine you are just on the street talking to regular people, imagine you are talking immediately with your friends. The core of all of this is simply that you don't know how you sound, and as such you don't know where to start. Even if you sound completely "normal", start working around it.
A brainless exercise you can do is to just record yourself copying various lines from characters you're aspiring to sound like, and make sure you always hit these three points in each copy:
>Full Kayfabe, hammy, in-character>Totally natural, as if you're talking to yourself in the shower>Conversational, as if you're speaking to another individualYou'll learn how you sound much faster than you realize. Start with that, and don't contextualize it around a "VTuber Voice". You need to start by first knowing your own voice before you even try to apply it to something. Once you know how you sound, then you follow it by leaning more and more into your character while knowing your own voice. After you feel comfortable with your vocal range as your character, then you wanna do practice as your character until it's natural. That's how any and all VTubers with a name do it. Nobody has a "Vtuber Voice", they've just become comfortable being who their character is, as well as adjusting in their professional career.