To help you, we need the following info to understand what your problem is.
If the plane ready to fly weighs above 70 grams, chances are poor it will fly.
What is your weight?
So do the following:
1) Take pics of top, side, front view of your bird.
2) Tell me which motor has what prop on it.
3) Where is CG.
4) Show video of you flying it.
How this plane is to fly is based on this:
At half throttle, you release it and it should fly level and straight forward.
If you increase throttle, it will climb.
If you back off throttle less than half, it will descend. Do not shut engine off until it is about ready to land.
To make turn, the rudder has a low and high rate. Select what is best for you.
Note:
When throttle is at zero or at the top and your add rudder, your plane will go crazy. If at bottom, will likely crash, at top, does some funky flying and tough to get control of.