When a resubmission happens, many teachers will view the most recent submission first. The only reason I would go back to a prior submission is if the student tells me to look at something there, or a student fails to fully resubmit (only submitting things they missed the first time). At times, it can be beneficial, showing that you are attempting to not only do the work, but improve on the work.
There is not a way for you or the teacher to remove the first submission. However, as @Chris_Hofer mentioned, talk to your teacher about how they handle resubmissions. Unless they turn it off, basic assignments usually allow for multiple submissions by default. You would see a button at the bottom of the assignment to resubmit.
