hi

can we say:

bak kızımı ne güzel! to say look how beautiful my daughter is..

and why do we say yatmam lazım?

I mean yatmak is to sleep so we should say yatmıyorum lazım... or somethıng similar but yatmam is like adding the m for possession and that´s done for adjectıives not for verbs..

please explain!! and thank you very much..

These are ways of expressing necessity.

For both lazım (noun) and gerekiyor (verb) the correct forms are like the examples below

Fiil (verb) + ma/me (infinitive) + kişi (person)

Benim çalışmam lazım/gerekiyor

Senin çalışman lazım/gerekiyor

Onun çalışması lazım/gerekiyor

Bizim çalışmamız lazım/gerekiyor

Sizin çalışmanız lazım/gerekiyor

Onların çalışmaları lazım/gerekiyor

The meaning is the same for both lazım and gerekiyor, with my teacher suggesting that lazım is used more on the streets, and gerekiyor is more academic, used in books and articles.

You are correct in suggesting the ´m´ indicates the person, and 

yatmam = my going to bed, my lying down

yatmam lazım = I have to lie down, I have to go to bed.

uyumak = to sleep

thank you very much.

and can anyone give me a reply for the first question please?

ne guzel is how beuatiful i know that now but do we have to say bak kızımı? or bak kızım because kızım ıs a dırect object correct? so we should add an ´i´ at the end..

Bakmak uses the dative a/e (to or towards) suffix on the direct object

Bana bak! = Look at me! (look towards me)

(Benim) kızıma bak = Look at my daughter