Can any artists offer guidance to a wanna be?

Here recently I’ve hit what I’ve felt was a growth spurt with my work. I find myself tattooing fake skin and drawing every moment I get a chance. To where I get up at 430am just to make more time to work. Above is an example of my last weeks practice . My questions are,

At what point did you feel like you were ready to pursue that apprenticeship?

How did you pick your mentor?

How many pieces did you include in your portfolio? Should they be watercolors or can I mix and match charcoal pastels?

I respect the hell out of these artists and I don’t want to waste anyone’s time ya know. Any information/ input is hugely appreciated

Thanks