na meka hama uni rkakma wage illanawa phd welata loke. ekai baluwe wistara
only US/canadian universities and a very few euro countries ask for gre. aus/uk/nz don't ask for gre.
it has quantitative reasoning (maths), verbal reasoning (english reasoning) and analytical writing. verbal reasoning is definitely harder than toefl.
most people self study for the test. it's an online test and you can register at an exam center to take the test (usually offered multiple times per week).
no point looking for 'past papers' because they change the questions time to time and it's not like a regular exam which is held every year...
do practice questions... download the official guide from ETS... find manhattan review 5 lb gre questions book... read princeton review gre book.
find a gre vocabulary android app and study the words...
write a few essays for analytical writing...
basically you need practice..