Surveys significance level

Hello,

Excel newbie here (and statistically almost illiterate). I just have very basic problem that I am not sure how to get significance level for my survey. I have 21 questions and the answers are in binary format 0 or 1. I have 42 counts for all of the questions and now I would like to get the significance level for each of the question. I have already ran T-test. Thanks for your help in advance!

EDIT: I have ran the T-test for the different groups I have, the first one has 25 correspondents and the second 17, but I would like to have significance level for the whole set of 42.