Although I am not familiar with assembler, I found the following codes for you. Let me know if that helps.
.model small
.stack 100h
.code
start:
; read character from keyboard
mov ah, 1h ; keyboard input subprogram
int 21h ; read character into al
; save character while we display a Return and Line-feed
mov bl, al ; save character in bl
;display Return
mov dl, 13d ; dl = CR
mov ah, 2h ; display subprogram
int 21h ; display CR
;display Line-feed
mov dl, 10d ; dl = LF
mov ah, 2h ; display subprogram
int 21h ; display LF
; display character read from keyboard
mov dl, bl ; copy character to dl
mov ah, 2h ; display subprogram
int 21h ; display character in dl
mov ax, 4c00h ; return to ms-dos
int 21h
end start