We call Allah(swt) the creator. The definition of creator is someone or something that made something into existence. Now when Allah(swt) creates he says be and it was. So for the first creation to ever existence he had to make a command for it to be created that command is “be.” Ok so before he created that first creation he wasn’t a creator by definition.

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Before the creation of the first creature, Allah Almighty was creator by force, not deed, just as before you had your first child, you were a father by force, not deed.
And when you had the first child, you became a father by deed.

Let me give you another example.
Sometimes you have money in your hand that suffices your needs for a whole year. Here we say about you that you are already rich, and it is not permissible for you to take zakat – for example -.
While, sometimes you do not have this money in hand now, but you have a job from which you get a monthly salary that meets your monthly needs. Here we do not say about you that you are really rich, but we say that you are rich in strength, and therefore it is not permissible for you to take zakat either, and if someone gave you something from zakat, you would say to him, praise be to Allah, I am rich and I do not deserve zakat.
I hope the picture is clear.