As you can see, we've already added one, so we don't need this new one that we've automatically created. First of all, you want to make sure that you've added Drumaxx to your default FL Studio project by going up to the Channel rack, pressing the Add new channel button, and selecting Drumaxx from the drop-down menu. One great way of doing this is to use the default plugin Drumaxx that comes bundled with the program by default.
There are multiple ways of getting started building basic beats in FL Studio.