Greetings.
"I" singular is used to emphasise GOD Alone always. Example:
20:14
"I am God; there is no other god beside Me. You shall Ubud Me alone, and observe the Salat to remember Me.
إِنَّنى أَنَا اللَّهُ لا إِلٰهَ إِلّا أَنا۠ فَاعبُدنى وَأَقِمِ الصَّلوٰةَ لِذِكرى
"We is used either as a "Royal We" for God Alone, like 50:16
We created the human, and we know what he whispers to himself. We are closer to him than his jugular vein.
وَلَقَد خَلَقنَا الإِنسٰنَ وَنَعلَمُ ما تُوَسوِسُ بِهِ نَفسُهُ وَنَحنُ أَقرَبُ إِلَيهِ مِن حَبلِ الوَريدِ
Or as "we" when also the Angels take part by GOD s order depending on the context of verses with "we"
Example- Where both "I" and "we" are used in the same verse:
41:12
Thus, He* completed the seven universes in two days, and set up the laws for every universe. And we adorned the lowest universe with lamps, and placed guards around it. Such is the design of the Almighty, the Omniscient.
فَقَضىٰهُنَّ سَبعَ سَمٰواتٍ فى يَومَينِ وَأَوحىٰ فى كُلِّ سَماءٍ أَمرَها وَزَيَّنَّا السَّماءَ الدُّنيا بِمَصٰبيحَ وَحِفظًا ذٰلِكَ تَقديرُ العَزيزِ العَليمِ
God alone created the universe (18:51), but the angels participated in handling certain jobs in the lowest universe.
In 20:81:
Eat from the good things we provided for you, and do not transgress, lest you incur My wrath. Whoever incurs My wrath has fallen.
كُلوا مِن طَيِّبٰتِ ما رَزَقنٰكُم وَلا تَطغَوا فيهِ فَيَحِلَّ عَلَيكُم غَضَبى وَمَن يَحلِل عَلَيهِ غَضَبى فَقَد هَوىٰ
The "we" is for GOD Alone and the Angels , part of the "Sujud to Adam" GOD uses them to help Beni Adam on earth like driving the clouds for rain, messengers , ...etc..
GOD bless you..
Peace.
