We are Iranians, want to go to Wuhan to support our team, how can I get a China visa untill 11 September?

Good day, I want travel to China Wuhan with my husband and my 11 year daughter for Asian basketball games because my son is one of the player of basketball national team and we waant go there to support our team especially my son would you please help me and say if we could get china visa until 11 Sep? and if we could get it by ourselves or better to get it by travel agence ? thank you for your time and help
Roya Kianafraz