Your teacher is probably thinking of the so-called conditional 1 (first conditional) sentences in which will appears only in the main clause. Example:
If you help me, I'll help you.
But your sentence is not a typical conditional. It does not mean:
Ms Taylor will see you now, on condition that you come this way.
Ms Taylor is ready to see you now. Please come this way.
"If you will come this way" is simply a polite way of saying "Follow me!"
You can read about different ways of expressing requests politely on the Cambridge Dictionary website. It includes this extract:
In speaking, we often use if followed by will, would, can or could to introduce a polite request:
If we can move on to the next point for discussion. (more polite than Can we move on …)
If I could just say one more thing … (more polite than Listen to me, I want to say something.)
If you will follow me, please. (more polite than Follow me, please.)