Guru Gobind Singh Indraprastha University

Well the institute is good and decent and will provide you with good facility and infrastructure which you require. But placement are not good as compared to other same level university or college .
There are no 100% placement not because of college but because of the students who are not able to perform during the campus selection and they blame the college for not providing the opportunity. The institute invites company for placement with decent package but then it is up to the candidate to perform in the selection process.
The major recruitment agency are HDFC, ICICI, ECLERX, ALLSTATES, Mahindra,TCS, Wipro etc.
The highest package is about Rs 8 lakh and the average package is about Rs 4 to Rs 5 lakh .
The minimum package offered is Rs 4 lakh. About 85% seats are reserved for Delhi candidate so it is not bad for them to get a package of Rs 5 lakh in Delhi only.
Hope this information helps.
All the best!!

Since 3 months is a long time. It is enough to go through each and every topic mentioned in the IPUCET curriculum. I would recommend you to join a crash course program from some of the good and reputed coaching centre close to your home (as I would not want you to waste your time in going from home to classes and vice versa).
Now, you should consider solving this book:
GGSIPU Engineering Entrance Exam 2017 solved papers: 2016-2004.
https://www.amazon.in/dp/9386179040/ref=cm_sw_r_cp_apa_i_tVLVzbXS32R5AI would also recommend you to go for some of the best books in each subject: S. L. Arora for physics, NCERT for chemistry, R. D. Sharma competitive level for maths, but go for these only if you have enough time left with you after you are done with Arihant.
Lastly, you need to keep a positive frame of mind during the last few days and should start solving mock test papers to gain confidence and to get an idea of how you should manage time during the examination.
I hope you do well.
Cheers.