Is it necessary to fill all the information while registering for ACT?

While registering for the test, they ask lots of questions regarding your interest, college plans, extracurricular activities etc. I simply don’t know everything about myself and don’t want to fill fake information about myself.
Also they ask for high school grades and GPA and in my country (India), we receive CGPA out of 10 (where 9 CGPA is grade A2 and 10 CGPA is grade A1. I don’t know what grade is intermediate between them). This was for classes 9th and 10th.
While for 11th and 12th, we are given percentages.
Is there any way I can know how to convert these CGPAs and %ages to 4 scale GPA?
I am in 12th class and my final examinations are not yet over hence I don’t yet have results of class 12th.
Please tell me should I leave these things and register for test or should I fill them anyway with approximation? Does ACT give time to fill this information after receiving the scores or after the test?
WILL THIS INFORMATION HAVE ANY IMPACT ON COLLEGE ADMISSIONS?
thanks.

You can skip all of that extra stuff. It is just to collect information that ACT uses for its own purposes. None of it will affect your college admissions.

Thanks, I was also thinking the same but on the page where we have to enter our grades, it says that it calculates the unweighted GPA from it and sends to colleges. Do the colleges have such sections in their application form?

You will have to send your transcripts to the colleges yourself when you apply. ACT can’t do that for you.

What ACT can do with your grades is use that information to organize lists of students with certain grades and test scores to sell to the colleges that are looking for students. So, if you like getting a lot of junk email, give ACT some version of your grades.

Thanks, I hope same applies for SAT as well.