Is there a setting to make it start with 0 not 1? 
What I actually want is use the number(s) on the left to count the number of rows in my table, but if I add names of columns in the first row, the count would be the number on left - 1. I could just deduct 1 each time or add extra column for count but I’d like not to, as, or especially as, there’s alread number column right there.
Don’t use the number(s) on the left to count the number of rows - it’s just half of coordinate of cell. To count rows use ROWS() function; to count values in cells of this rows use COUNT() function; to count values and strings use COUNTA() function; to count blank cells use COUNTBLANK() function…
No, you won’t be able to renumber the lines - and that’s very good! Otherwise, you would be confusing spreadsheet users around the world.
Alright, thank you. I just wanted to be able to get the count of rows at glance without extra steps or extra columns.