If you want to populate weekdays (Monday to Friday) in a range, follow below steps.
Step1: In Cell A1 write any month 1st date. Let’s say 02/01/2017 (Feb 1st 2017)
Step2: In Cell C1 write this formula =WORKDAY.INTL($A$1,IF(OR(WEEKDAY($A$1)=1,WEEKDAY($A$1)=7),ROW(A1),ROW(A1)-1),1)
Step3: Drag Cell C1 formula down…Check the below screenshot