How to read a row one by one in the for loop

Hello,
I want to use the For Loop and print a row one by one whatever i required.
here is my code:

import csv
with open("details.csv") as csvFile:
    reader = csv.DictReader(csvFile)
    for row in reader:
        #print(row['Name'], row['age'], row['DOB'])
        if['age'] == '21':
            print(row['Name'], row['age'], row['DOB'])
        else:
            continue

Here i want run the for loop until 6 times and also i want specific data of who ever age is '21', that person details only i want print, if it is other than '21' then skip the row. but my code is doesn't perform exactly like i want.
can anyone help me..?
Thank you :)