I’ve had bad luck too. One $180 drone was so bad, it tried flying away on its own. I’ll never spend that much on a drone again.
DJI is great unless it ends up in a lake or crashes into a building. Then you’ll wish you bought something cheap instead of a $600 DJI.
Your cheap controller probably has trimming buttons. Press the opposite direction of where it’s drifting, and it should fix the issue after a few clicks.
Finally, a useful answer!
You can cut it, but it won’t help anything 
That’s the fuse to start the engines. Light it and watch the sparks fly
Looks like you’ve got a boy drone there!
That wire? That’s your antenna.
It’s an antenna. Don’t cut it, it needs to be that length.
That’s the starter cord. Give it a pull to fire up the motors!
Cheap drones are hit or miss. I’ve had three of the same model, and only one flew straight.
Looks like a bad home job cutting the umbilical cord! People just don’t know enough about drone ‘breeding’ these days, smh.