What good portfolio examples have in common
They say who the person is and what they do in the first screen. They show a few projects in depth and leave out the rest. Each project explains the person's own part in it, not only what the team made. And there is one obvious way to get in touch.
What to look for when you compare examples
Check how fast you find the work. Check whether the page still reads well on your phone. And ask whether the style suits your field: a bold, playful page can suit a designer and distract from a finance student's work.
Do not copy the words of an example. Copy its structure, then write about what you really did.