I am preparing for jeemain July. Now I am writing mocks three days once. I am not getting all the questions in the mocks. Can I leave the exam upto what I and submit the exam. So, there will be sometime for preparation. Is it good thing to be followed. Give me a suggestion to my query.

Hello.
Yes it is good thing that you are going for mock test for the preparation of JEE Mains, if you are not getting any question in this then you should write down it so that you could solve it after, and if it is about submission then you can go with hit and trial, those questions which you were not getting before hope you would be able to solve these after clearing your concept, you can also take help of  online tutorials.
Best of luck