Eid al-Fitr is one day, which is the first of Shawwal, and fasting on this day is prohibited. According to Grand Ayatollah Khamenei, fasting on the following days is forbidden: 1. The day of Eid al-Fitr. 2. The day of Eid al-Adha. Source: [Message on Prayer and Fasting, Issue 976](
https://www.leader.ir/ar/book/196/1?sn=31851). Grand Ayatollah Sistani also states that fasting on the two Eids, which are the 1st of Shawwal and the 10th of Dhul-Hijjah, is prohibited. Source: [Official Website](
https://www.sistani.org/arabic/qa/0571/). May you be successful in all good.