Hi Shadab,
For the required fields (LGORT and BWTAR) in TCODE VL03N, press F4 in debugging mode, you can find the used FM which provides F4 help. Below snap of code can be a reference for you to proceed further.
*Valuation Type
CALL FUNCTION 'RV_HELP'
EXPORTING
key = help_lips-matnr
key2 = t001w-bwkey
key3 = help_lips-bwtex
number = '014'
trtyp = t180-trtyp
field_in = help_lips-bwtar
IMPORTING
field = lips-bwtar.
*Storage Location
CALL FUNCTION 'RV_HELP'
EXPORTING
key = lf_matnr
key2 = lf_werks
key3 = lf_vgbel
key4 = lf_charg
key5 = lf_sobkz
number = '011'
trtyp = t180-trtyp
field_in = lf_lgort
description_in = t001l-lgobe
IMPORTING
field = lips-lgort
description = t001l-lgobe.
Regards
Pallavi