I just looked at that plane at the link you provided. Being a tail dragger your wing is starting out at a positive angle of attack. This is causing the premature take off. If you are taking off from the ground you have to get the tail up so the wings get level and build up some speed while you are on the ground then gently pull back on the elevator to slowly lift off. As simple as that sounds it can be a lot to manage and takes a lot of control for a beginner. I recomend you hand launch this plane for now untill you get used to the controls. Run the throttle up to full power and toss the plane into the breeze at a slightly upward angle, maybey 10-15 degrees upward. Only toss it as hard as you would throw a nerf football to a 5 year old standing 20 ft away from you. Don't throw it as hard as you can.