Husayn radi Allaahu anhu was killed in Iraaq in Muharram in the year 61 after hijrah and his body was buried in Iraaq.
As for the claim that his head was transported to Egypt and buried there, then we do not know any basis for this – and indeed some of the muhaqqiqeen (verifiers) from the people of knowledge have rejected this.
Your not knowing this will not harm you.
That which is legislated upon you - and other than you from the Muslims – is being pleased with him and with the rest of the Companions of the Prophet sal Allaahu alaiyhi wa sallam – may Allaah be pleased with all of them.
And with Allaah is the tawfeeq. And may peace and blessings be upon our Prophet, Muhammad and upon his family and Companions.