It normally can come out the bottom or top of the fuselage. It is okay to hang down but can be easily stepped on. Put the wing on the fuslage. Make sure the aileron torque rods do not interfere with the other servos. Check that the aileron servo is connected to the receiver aileron extension connector.
Trainers usually use rubber bands to connect the wing to the fuse.
Reason, during a crash or bad landing the wing can pop off with little damage. It is quicker and easier to make a repair to the fuse than the wing. If you multiply the weight of the plane by 1.5 and round that off to the next even number, you will have a good count for the number of rubber bands needed to hold the wing. Install the first two straight across, the next pair criss cross and continue to alternate. Make sure the fuel tank is empty.