Which topics should we learn from the topic Constitution for clat ?

Hello Vanshika,
Hope you are doing good.
So, generally there is no such thing called syllabus for the CLAT. However, for the purpose of general knowledge section, you will have to study, Constitution, Current affairs,   Static GK, History and Geography as well.
So it's not about topics, just read everything barely and get to know the gist of the subject. That's it. For this you remember certain important articles like articles related to fundamental rights, fundamental duties, appointment and impeachment of judges, president, etc. Appointment of election commissioners, their powers and all. Just have in your mind the articles related to them and the powers entrusted with such articles.
Good luck!!