Dear, below I will provide you with link to download sample questions.
https://engineering.careers360.com/download/jee-main-sample-papers-previous-years?icn=JEE-Main_sample_paper&ici=JEE-Main_exam-view_sticky

There is nothing called important questions. questions which are important for some may not be important for others. All you need to do is be thorough with what you have studied and practice more problems to get acquainted with the exam pattern. You sholud brush up your memory and have your basics cleared. Dont panic. With little practice you will get through it. Best of luck