When I load up the world I have gamemode creative, I can just fly up to the Finish line, and break blocks.... What do I do? Edit : The title - Am I supoosed to have /gmc

You can use creative mode to practice your runs and explore the map, but whenever you are recording a run and you want to submit it, you first have to open to LAN and enable cheats so that you can set your gamemode to 0 or 2. Those are the only acceptable modes for submitted runs.