which subject is usually tough in neet, Jee mains and advance and give the reson

Hello aspirant,if you prepare in the correct manner and build your foundation strong in the subject you are studying no subject will be tough.But where mostly students secure less mark and you need to persevere more  is Physics because it requires a deep understanding and in-depth knowledge and generally questions are tricky in Physics.But if you work hard right from the beginning you can crack it easily.
Hope this helps!