I’m myanmar passport holder, do i need to apply transit visa

Dina, your itinerary is definitely eligible for 24 hour visa free transit and you do not need any kind of visa.

If you plan to exit the airport in Guangzhou you will approach transit counter as soon as you land in Guangzhou. There you will apply for a temporary entry permit for free by presenting your flight tickets.

Alternatively you can stay at the airport, airside and wait for your connecting flight. Im this case you do not need to perform any formality.