Usually "drawing a portrait" means also the sketching stage, so this is more of a "how to color a portrait".
But let's get back to the topic.
First thing I want to mention is... your additional notes & sketches in between the tutorial frames. I feel like they need their personal space (especially those colors that lay under the text).
Next, the positioning. The right side of the picture looks heavy and pressing to the left (and her whole body looks like leaning, I guess that wasn't intended?). If not to change background: make three imaginary vertical lines that cut the piece in equal parts, it would be better to place her head at the right line.
The anatomy is fine (thought her left eye isn't at the right place
What is best about the tutorial - is how detailed and clear it is! To my mind, this is obligatory to be understandable.
Also, the tutorial page looks messy and the mixture of typed and written text looks like it is still a rough copy of it.
(also, I can help u with english