Nose, eyes, lips: together they cover pretty much everything that trips people up when drawing a face, and each one follows the same Theory → Simplification → Expression flow, so once you're used to it in one guide, the next two feel familiar rather than like starting over. I'd recommend picking one feature and finishing it properly before jumping to the next — resist the urge to skim all three at once. However you tackle it, take your time, compare against the references, and don't stress over the early attempts. Excited to see what you build with all three in hand!