Thank you Rick, you have given so many helpful tips here in this blog. Would appreciate one more help:
With the code provided, I understand we use IML to output in dataset. However can we create a excel or pdf output using ODS with all the variables in row and 4 columns - variable name, missing count, non-missing count and percentage missing. and What if I need to order the output with the sequence of questions asked in the questionnaire?

proc format;
value $missfmt ' '='Missing' other='Not Missing';
value missfmt . ='Missing' other='Not Missing';
run;

proc freq data=one;
tables _all_ / missing missprint nocum nopercent;
format _NUMERIC_ missfmt. _CHAR_ $missfmt.;
run;