"Say, is there any of your partners who begins creation and then brings it back?" meaning: who creates, then causes to die, then brings back to life? That is to say: they do not have the power to do that.
"Say, Allah begins creation and then brings it back, so how are you deluded?" meaning: how are you turned away from Him?!
﴿قُلْ هَلْ مِنْ شُرَكَائِكُمْ مَنْ يبدؤ الْخلق ثمَّ يُعِيدهُ﴾ أَيْ: مَنْ يَخْلُقُ، ثُمَّ يُمِيتُ، ثُمَّ يُحْيِي؛ أَيْ: أَنَّهَا لَا تَقْدِرُ عَلَى ذَلِكَ.
﴿قُلِ اللَّهُ يبدؤ الْخَلْقَ ثُمَّ يُعِيدُهُ فَأَنَّى تُؤْفَكُونَ﴾ فَكيف تصرفون عَنهُ؟!