The word “Sunna” means “The System/The Way”, and therefore “Sunnat-Allah” “The System/The Way of Allah” With this meaning the “Sunna” is only for God. Because he is the “Ultimate System/Way Giver”
Sunnat-Allah has been described in Al-Quran as:
Chapter 17: Verse 77
سُنَّةَ مَن قَدۡ أَرۡسَلۡنَا قَبۡلَكَ مِن رُّسُلِنَاۖ وَلَا تَجِدُ لِسُنَّتِنَا تَحۡوِيلًا
Chapter 33: Verse 38
مَّا كَانَ عَلَى ٱلنَّبِىِّ مِنۡ حَرَجٍ فِيمَا فَرَضَ ٱللَّهُ لَهُۥۖ سُنَّةَ ٱللَّهِ فِى ٱلَّذِينَ خَلَوۡاْ مِن قَبۡلُۚ وَكَانَ أَمۡرُ ٱللَّهِ قَدَرًا مَّقۡدُورًا
There is not to be upon the Prophet any discomfort concerning that which Allah has imposed upon him. [This is] the established way/system of Allah with those [prophets] who have passed on before. And ever is the command of Allah a destiny decreed.
Al-Ahzab 33:62
سُنَّةَ ٱللَّهِ فِى ٱلَّذِينَ خَلَوۡاْ مِن قَبۡلُۖ وَلَن تَجِدَ لِسُنَّةِ ٱللَّهِ تَبۡدِيلًا
Chapter 48: Verse 23
سُنَّةَ ٱللَّهِ ٱلَّتِى قَدۡ خَلَتۡ مِن قَبۡلُۖ وَلَن تَجِدَ لِسُنَّةِ ٱللَّهِ تَبۡدِيلًا
There is no word found in the Al-Quran about Sunnat-E-Nobi. Prophet’s/Rasulullah’s can’t give any system/way according to verses of Al-Quran.
Chapter 69: Verses 44-47
(44) وَلَوۡ تَقَوَّلَ عَلَيۡنَا بَعۡضَ ٱلۡأَقَاوِيلِ
(45) لَأَخَذۡنَا مِنۡهُ بِٱلۡيَمِينِ
(46) ثُمَّ لَقَطَعۡنَا مِنۡهُ ٱلۡوَتِينَ
(47) فَمَا مِنكُم مِّنۡ أَحَدٍ عَنۡهُ حَٰجِزِينَ
(44) And if he (Messenger)had made up about Us some [false/fabricated] sayings,
(45) We would have seized him by the right hand;
(46) Then We would have cut from him the aorta.
(47) And there is no one of you who could prevent [Us] from him.