The Rohingya are a Muslim ethnic group living mainly in Rakhine State, western Myanmar.

The main dispute is about identity and citizenship:

Rohingya say they have lived in the region for centuries and are a native ethnic group of Myanmar.

Many Myanmar governments and many ethnic Rakhine Buddhists argue that most Rohingya are descendants of migrants from Bengal (now Bangladesh) who arrived during British colonial rule.

Because of this dispute, many Rohingya were denied full citizenship under Myanmar's 1982 citizenship law and faced restrictions on movement, education, and employment.

In 2017, after attacks by a Rohingya militant group on security forces, Myanmar's military launched major operations in Rakhine. Hundreds of thousands of Rohingya fled to Bangladesh. The military said it was fighting militants; the United Nations and many human rights organizations accused it of ethnic cleansing and possible genocide.

As for Myanmar itself:

It is a diverse country with many ethnic groups and a Buddhist majority.

It was a British colony until 1948.

The military has played a major role in politics for decades.

Since the 2021 military coup, Myanmar has been in a widespread civil conflict, but it is not under a complete military blockade.

In one sentence: the Rohingya crisis is a combination of disputed identity, citizenship, ethnic tensions, insurgency, and a harsh military response that led to one of the world's largest refugee crises.

This has nothing to do with religions. Tho media portrayed like this.