Hello,

Joining a coaching or not actually depends on what you want.If you feel you will be able to cover the syllabus,understand the concepts on your own by refering to some books,sample papers on the net or by seeing videos on youtube it is fine if you do not take coaching.But if you  are not taking coaching you have to stay dedicated and work hard daily because in a coaching you get to cover a topic and solve homework questions daily whithout any excuse and hence a regularity in studies is maintained.

So the main thing is being regular in studies,if you feel that you would not be able to be regular in studying by yourself or that there will be distractions you can join a coaching.But joining a coaching is not compulsory.

You can copy paste and go to this official link to know the new syllabus for the entrance test for the current year- https://jnu.ac.in/admission/e-prospectus-2019-20.pdf

Refer to page 133 in the above pdf to know the syllabus of International relations.

All the Best!