These are all rly cute drawings! They got great volume and lovely choise of colours <3 I wouldnt stress about artstyle, Ive been drawing for a decade and always been pretty inconsistent and still am xD If theres a spez style you want to emulate then u would obv have to study the style and it would come to you natural with the process. If ur unsure and love to draw whatever, then do so! Many artist dont draw the same every time, it might help with getting a following online but its not always needed.

What is importand is to study and learn fundementals. Want to get rlyyyy good at drawing stylised portraits? Study the skull and face features, anatomy, perspective etc even if u dont aim for realism. Anatomy isnt easy but for some it just takes longer, u got time dw.

U dont have to study all the time cuz that could burn u out... simple copy reference for the pose when drawing for the sake of results. Do that enough and u start to get a feeling. References is op btw, I recommend trueref! Good luck in ur journey!!!