There is already one review article on a topic of interest published few years ago. I want to write a review paper on that broad topic with some new insights.Can I cite the papers that are already used in that older review article?? Or should I only use the newer research articles which were available after the publication of the older review article??
If you're writing a new comprehensive review on the same subject you'll probably end up citing many of the same references. To be explicit, yes, you are allowed to, and supposed to, cite relevant literature. Suppose instead that your review article focuses on newer developments, or some specific aspect. Then you can refer the reader to the old review paper, and include references to the most important papers therein. No matter the form you choose, I would be very surprised to see two reviews in the same field with zero overlap in choice of references.
A related question is when a new review is justified. There's a nice discussion in A systematic review already exists in the literature. When is a newer one required?
Of course you can cite papers that are used in the older review article. But if the older review is well done, it should dispense you from reading most of them. And therefore also from citing most of them. On the other hand, if your viewpoint differs from the older review's in some respects, then you may have to do your own synthesis of some of these papers, and therefore to cite them.