I attended the 'Id (prayer) along with 'Umar. He offered prayer before the sermon. He then said: The Messenger of Allah ﷺ prohibited fasting on these two days. As regards Id al-Adha, you eat the meat of your sacrificial animals. As for 'Id al-Fitr, you break (i.e. end) your fast.
شَهِدْتُ الْعِيدَ مَعَ عُمَرَ فَبَدَأَ بِالصَّلاَةِ قَبْلَ الْخُطْبَةِ ثُمَّ قَالَ إِنَّ رَسُولَ اللَّهِ ﷺ نَهَى عَنْ صِيَامِ هَذَيْنِ الْيَوْمَيْنِ أَمَّا يَوْمُ الأَضْحَى فَتَأْكُلُونَ مِنْ لَحْمِ نُسُكِكُمْ وَأَمَّا يَوْمُ الْفِطْرِ فَفِطْرُكُمْ مِنْ صِيَامِكُمْ