She can do what she wants" vs. "She can do whatever she wants to". Is there any subtle difference?
She can do what she wants." vs. "She can do whatever she wants to". Is there any subtle difference, maybe in emotion? Are they used in different contexts? Also, is 'do' necessary at the end of the sentence, as in- "She can do what she wants to do."?

Question

She can do what she wants" vs. "She can do whatever she wants to". Is there any subtle difference?
She can do what she wants." vs. "She can do whatever she wants to". Is there any subtle difference, maybe in emotion?  Are they used in different contexts? Also, is 'do' necessary at the end of the sentence, as in- "She can do what she wants to do."?

Answer

You don't need "to" or "do" at the end of either sentence - the meaning is clear without these words.

Both have the same meaning, except that "whatever" gives more emphasis to her freedom.