When you write
for line in modo:
filezise+=1
You have already consumed the file.
If you want to consume it again, you need to do modo.seek(0)
first to rewind the file back.
If you do not rewind the file, the line below will return an empty string, because there is nothing left in the file.
readit = str(modo.readline())
Of course, there's no real need to go through the file twice. You can just do it once and append to your lists.
column1 = []
column2 = []
for line in modo:
filezise+=1
column1.append(line[0])
column2.append(line[2])