How to add text to OS written in Assembly : So i started learning assembly and am writing a simple OS with FASM i have a blue screen with a gray top bar and a curser but cant get text to appear on a line. on the top line i want it to say FILE SYSTEM and then on other lines i want stuff. Ill put the code here:

    mov ax, 9ch
    mov ss, ax
    mov sp, 4096d
    mov ax, 7c0h
    mov ds, ax
    ;----------------


    ;this sets blue to background
    mov ah, 09h
    mov cx, 1000h
    mov al, 20h
    mov bl, 17h
    int 10h
    ;end of blue

    ;start of gray top
    mov ah, 09h
    mov cx, 80d
    mov al, 20h
    mov bl, 87h
    int 10h
    ;end of gray
    ;top bar






    ;end of top bar
    ;define mouse
    mov ah, 01h
    mov cx, 07h
    int 10h

    mov bl, 5h
    mov cl, 5h


    _mouser:
    mov ah, 02h
    mov dl, bl
    mov dh, cl
    int 10h

    mov ah, 00h
    int 16h

    cmp al, 77h
    je _up
    cmp al, 73h
    je _down
    cmp al, 61h
    je _left
    cmp al, 64h
    je _right
    cmp al, 20h
    je _click
    jmp _mouser



    _click:
    mov ah, 0eh
    mov al, 0b2h
    int 10h
    jmp _mouser

    _up:
    cmp cl, 0h
    je _mouser
    sub cl, 1h
    jmp _mouser

    _down:
    cmp cl, 24d
    je _mouser
    add cl, 1h
    jmp _mouser

    _left:
    cmp bl, 0h
    je _mouser
    sub bl, 1h
    jmp _mouser

    _right:
    cmp bl, 79d
    je _mouser
    add bl, 1h
    jmp _mouser



    ;----------------
    times 510-($-$$) db 0
    dw 0xAA55

i have tried
    mov ah, eof
    mov al, 'F'
    int 10h

problem is i cant make a string and i know you cant do it with MOV AH, EOH
