Hello Muh,
You can use the following formula to show values based on the Month and Employee.
Formula:
=LET(
combined, VSTACK(Jan:May!$D$5:$P$26),
header, Jan!$D$4:$P$4,
selected_employee, $D$4,
selected_month, UPPER(TEXT(DATEVALUE("1-" & $B$4), "mmmm")),
month_col...