Bismillah.
I do understand that celebrating one's birthday is Haram. So what about celebrating an institution's "birthday" (the date when the institution was established) by holding social/charitable acts?
For example, a school was established on 11 March 1970. And on March 2020 (not exactly on 11 March 2020) the school plan to hold a series of good events such as workshop on education, public Islamic lectures, charity, inviting orphans to the school and feed them together with the school's students and teachers.
Are those events have the same ruling as celebrating a person's birthday? Thank you

All perfect praise be to Allah, The Lord of the Worlds. I testify that there is none worthy of worship except Allah, and that Muhammad, sallallaahu 'alayhi wa sallam, is His slave and Messenger.

We do not see a difference between celebrating one’s birthday, taking it as a recurring festival, and celebrating the anniversary of the founding of an institution and taking it as a recurring festive occasion. Just as the former is impermissible, the latter is also impermissible; they are both festive occasions. Shaykh Ibn ‘Uthaymeen, may Allaah have mercy upon him, said: “Holding festive celebrations on specific days, months, or years to be celebrated as recurring festivals should be exclusively determined by the Sharee‘ah and not according to customs and traditions. This is why, when the Prophet came to Madeenah and found its people celebrating two days during which they engaged in play, he asked: ‘What are these two days (what is the significance)?’ They said: ‘We used to play on these two days during the (pre-Islamic period of) Jaahiliyyah.’ Thereupon, the Messenger of Allah said: ‘Allah has replaced them for you with what is better: ‘Eed Al-Adh-ha and ‘Eed Al-Fitr.’ Were festivals in Islam left to be determined according to customs and traditions, people would introduce festivals to celebrate every given event and, accordingly, the Islamic festivals enacted by the Sharee‘ah would have no significant value.” [End of Quote]

The school can hold these events at different times of the year without restricting them to the anniversary of its foundation day.

Allah knows best.