Can only sing in head voice

So i think my issue started around 9 or so… i realized i didn’t really sound good in chest voice/loudly/ a voice more close to my speaking voice and got used to singing in head voice even though i believe my voice is a bit on the low side of a woman. now i can’t sing in chest voice (i learned these terms recently so i might be using them wrong?) without sounding (to me, atleast,) like i’m just shouting/talking. it’s also harder to do vibrato and everything else i can do much easier in head voice. it basically feels like i don’t even know how to sing when i sing in chest voice. i’ve also noticed that although when i was younger i was a lot louder, now even when i try to shout nowadays it comes out much quieter. so my main question is just, is there a way for me to bridge the gap between my chest voice and head voice without it feeling like i basically have to relearn singing in chest voice? also what’s the difference between head voice and mix? tysm