if you can't find it on here, it's really damn cheap on amazon.. https://www.amazon.com/How-Draw-Human-Figure-Anatomical/dp/0140464778/
Most art schools (not high ones, but like... your avg art schools) are happy with this:
10 realistic sketches - like figure drawings, perspective drawings, properly shaded fruit etc
10 expressive pieces - anything you want. Get creative. Expressive colorful pieces, cartoony shit, whatever.
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If you don't know how to draw well or make anything, then you better get to work starting now. If 20 pieces of art in a portfolio is stressful to you, you're in for a rude awakening at art school.
I recommend getting a figure drawing book on amazon. Get "How to Draw the Human Figure: An Anatomical Approach" by Louise Gordon. (https://www.amazon.com/gp/product/0140464778/ref=ppx_yo_dt_b_asin_title_o00_s00?ie=UTF8&psc=1 ) It is like $6 and is the best investment you'll ever make.
So do that, get familiar with figure drawing, and learn gesture drawing as well. Build on the fundamentals! That shit is important.
If all of this sounds daunting to you and you prefer art as a hobby, go with a more stable career like Information Techology or go to a trade school for something like electrician work - shit's good money, and you can support your lifestyle and make art on the side (that's what I did, and I sure am glad I did it.)
For drawing faces, I highly suggest you learn to draw the human skull. I know it seems creepy, but I found it's the best foundation to which you start laying on the details of the face. When I first heard about the method, I drew a lot of skulls. I started laying the facial features we would normally see (eyeballs, nose, lips) and found that the face was structured quite well. Personally, I found the human skull provided better landmarks than the standard drawing faces tutorial.
I also have a life-size (plastic, please stop looking at me like that D:) skull to help me with certain details and figuring out other landmarks. I prefer to have a physical example of it, but that may be a remnant of the drawing courses I was made to take as part of my major. If you find pictures (even digital 3D models) aren't that helpful, then look to buy a skull. They usually sell them for medical (dental) students (I got mine at University of Toronto's bookstore, I think it was about 40 dollars).
Check out How to Draw the Human Figure. It does go beyond just faces, but they have drawings showing how the muscles lay on the skull and how the face looks once the skin is put onto it. It helped me a lot.
From that point on, I suggest you start making observations on how your muscles behave in different facial expressions. However, there is this nice large flowchart showing the different expressions (and grouped).
I hope that helped :)