Hi Anshika,
DATA: lv_field type c length 2,
lv_date type ekko-aedat,
lv_datemonth(30) type c.
IF lv_date+4(02) EQ '01'.
lv_field = 'st'.
ELSEIF lv_date+4(02) EQ '03'.
lv_field = 'rd'.
ELSE.
lv_field = 'th'.
ENDIF.
READ table itab(FM Internal table ) with key mn = lv_date+4(02).
if sy-subrc is initial.
lv_month = itab-ltx.
endif.
CONCATENATE lv_date+6(02) lv_field lv_month lv_date(04) into lv_datemonth.
Hope it helpful,
Regards,
Venkat.