Hi neha,
loop at itab1 assigning <fs1>.
Move corresponding <fs1> to wa_tab3.
Read table itab2 assigning <fs2> with key vbeln = <fs1>-vbeln.
if sy-subrc = 0.
move corresponding <fs2> to wa_tab3.
endif.
append wa_tab3 to itab3.
clear wa_tab3.
endloop.