Can you explain why those beliefs are subject to doubt?

Reading from your Exploring Philosophy textbook “Meditations on the First Philosophy”, First Meditation, ReneDescartes:Meditations on the First Philosophy”, Second Meditation, Rene DescartesIn Meditation 1, Descartes engages in the method of doubt. He examines all of his beliefs, and rejects any beliefthat may be false. If it is possible to doubt the truth of a belief, he gets rid of it. The goal is to be left with only thosebeliefs that are absolutely certain. In Meditation 2, Descartes continues doubting all of his beliefs, but he reaches aconclusion about the one thing he cannot doubt and about which he is absolutely certain.Which of the beliefs does Descartes question in Meditation 1? Can you explain why those beliefs are subject todoubt? What is he certain about in Meditation 2, the one belief he can be sure is true?