Dear Aspirant ,

In UPSC Preliminary exam , generally you have to prepare a vast syllabus within a very short time .. In this stage , you have to gain knowledge about all this topics and show that in your answer paper.. time management is also necessary to cut off prelims .. Within the given time , you have to answer the minimum questions that is required to clear the prelims i.e you should do the analysis of last year cut off s.

you can also go through this article that will help you for UPSC Preparation :

https://competition.careers360.com/articles/how-prepare-for-upsc-ias

Hope this helps !!

Best wishes !!