In Islamic theology, Allah did not “come from” anywhere. God is understood as eternal, uncreated, and the source of created existence. Asking what created Allah applies the logic of created things to the Creator, which classical Islamic theology rejects.

Allah is not a created being
Islamic monotheism teaches that everything dependent and created ultimately owes its existence to God. Allah is not one object inside the universe alongside other objects.
The Qur’an describes God as the First and the Last and repeatedly distinguishes the Creator from creation.
Surah al-Ikhlāṣ
Qur’an 112 gives one of Islam’s most concise statements of divine unity: God is one, self-sufficient, does not beget, is not begotten, and has no equivalent.
Muslims commonly use this passage to explain why God does not have a divine genealogy or origin story.
What about causes?
Ordinary things have causes because they begin, change, and depend on other conditions. Classical Muslim theologians and philosophers argued in different ways that the ultimate source of contingent existence cannot itself be just another contingent object.
Schools of kalām and Islamic philosophy developed different technical arguments, but they share the rejection of a created Allah.
Allah and the Arabic language
Allah is the Arabic word used by Muslims for God and is also used by Arabic-speaking Christians. The word’s linguistic history is separate from the theological claim that God is eternal.
Islamic belief therefore should not be confused with the history of how a word developed in Arabic.
Short answer
According to Islam, Allah has no origin, parent, creator, or beginning. Allah is understood as the eternal Creator rather than a being produced by the universe.