You are reading a tafsir for the group of verses 56:15 to 56:17
عَلٰی
سُرُرٍ
مَّوْضُوْنَةٍ
۟ۙ
مُّتَّكِـِٕیْنَ
عَلَیْهَا
مُتَقٰبِلِیْنَ
۟
یَطُوْفُ
عَلَیْهِمْ
وِلْدَانٌ
مُّخَلَّدُوْنَ
۟ۙ
3

The reward of As-Sabiqun

عَلَىٰ سُرُ‌رٍ‌ مَّوْضُونَةٍ ([ They will be sitting ] on thrones woven with gold...56:15) The word مَّوْضُونَةٍ mawdunah, according to Ibn ` Abbas ؓ ، as recorded by Ibn Jarir, Ibn Abi Hatim, Baihaqi and others, means 'fabric woven or inwrought with gold thread'.

وِلْدَانٌ مُّخَلَّدُونَ (...by Immortal boys...56:17) meaning that the boys will never grow up, get old or change in shape. The preferred opinion is that the youths of Paradise, like the fair damsels of Paradise, will have been born in Paradise. They will be the servants of the inmates of Paradise. Hadith narratives indicate that there will be thousands of such servants for each of the inmates of Paradise.