If God is one why is he referred to "we" in some ayats of the Quran?
for e.g this is ayat 23 from surah insaan
"Indeed, it is We Who have revealed the Quran to you ˹O Prophet˺ in stages."
Why is there "we" instead of "he" here?

When He addressed the believers through the prophet, He said 'We'.
When He addressed the non believers through the prophet then He said 'He' like here

Holy Quran 112:1
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قُلْ هُوَ اللَّهُ أَحَدٌ

Say, "He is Allah, [who is] One,