first MUN

So, it'll be my first MUN, around the end of may--im a part of UNGA(chile), now in the committe group thats there on whatsapp, some pdf's were shared regarding the background of the committee, like the angenda,problems etc.. basically everything.. theres ALOT, ALOT of information on there--so many topics so many things...now im confused as a first time MUN participant, or even if not, is reading the whole pdf by heart and making notes and stuff very precisely absolutely necessary? its 70 pages btw so you can imagine how detailed it is. also im in 11th grade. if any experienced delegate is there--I have few other questions so please dm me if youre okay w that.