awk output of a row in a column

Print the last line of the last one
NF is a column, $ NF is the last one

awk 'END{print $NF}'  /etc/passwd 

Printing the specified row of the specified column (e.g., column 3, line. 4)
NR row:
custom separator -F, -F: meaning is: a delimiter

awk -F： 'NR==3{print $4}'  /etc/passwd

awk process is divided into

B Egin performed once, read the first line of text statement, such as: awk 'BEGIN{print "User Uid Home"}'
{} performed row by row
END executed once, the result is generally a last line output