Who decides if the parties platform gets carried out? Is it the election board? The parties chairman the party members or the voters?

Ultimately, the responsibility for carrying out a party's platform lies with the party's elected officials, including the party's chairman, party members who hold positions of leadership within the party, and the voters who elect these officials. The election board is typically responsible for overseeing the electoral process and ensuring that elections are conducted fairly and according to the rules, but they do not have a direct role in implementing a party's platform. Ultimately, it is the elected officials who have the power to enact policies and initiatives that are in line with the party's platform.