There are very few things that we can say with absolute certainty about the ancient world, and Cleopatra's heritage and appearance are no exception. But there is a huge difference acknowledging that and saying that we just don't know anything about this topic.

We can say with a reasonable degree of certainty that Cleopatra was Greek and looked like what other Greeks looked like (and still look like).

Her, Ptolemaic dynasty rarely married outside and when they did, they married other Greeks. We also have her statues, busts and even paintings.

Cleopatra's bust A likely fresco of Cleopatra A likely painting of Cleopatra

On the other hand we have no reason to believe she had any black African heritage. So, she very likely looked "white" and even had red hair. Everything else seems to be wishful thinking.