Im making a mod for a communist revolution in Cuba but when i finish the national focus for cuba to start it. Nothing happens any ideas on how to fix?

I'm not sure you can use a normal civil war command for Cuba as it only has one state - Normal civil war mechanics require a state to have two states, where one state would rebel whilst the original country would hold the state with the capital.

I think the only way you can really do it with single-state countries is by having two countries, and then the "Civil War" starts out with you giving the "new" Cuba the province(s) it should start in with set_province_controller = PROVINCE_ID.

Give the new Cuba cores on the Cuban state, and then when the civil war is over, remove the cores for the Cuba that was defeated.