How to add 13.10 after reading character line?

I am trying to write an array of 40x20 characters, doing 2 cycles, in which character reads the character saves in a buffer, but I know we have to add 13,10 to change the line and the cursor back to the beginning. But is 13.10 considered a byte? How can I add 13,10 at the end of the line, ie after reaching the last character of the line.

Part of the code

xor cx,cx
xor si,si
xor ax,ax

mov cx, 20
forLine: 
    forColumn:
        mov         ah, 08h ; Guarda o Caracter que est� na posi��o do Cursor
        mov     bh,0        ; numero da p�gina
        int     10h 
        mov caraterLido, ah     
        mov buffer[SI], caraterLido
        inc si
        cmp si, 40
        jne forColumn
        //quando for igual a 40, adicionar 13 e 10 no fim da linha 

loop forLine