You're not anywhere close to being ready to take the test if you lack the fine control needed to drive smoothly and safely. Practice, practice, practice. Someone who catches on quickly still needs about 40 hours behind the wheel. Someone who doesn't, like you, needs at least twice that much practice.
You have been trying to drive without mastering the basics, and whoever is teaching you doesn't understand that. Go to a quiet street or parking lot and just practice accelerating and stopping straight ahead. Then, when you can do that smoothly, practice stopping at a specific spot. When you can do that smoothly, then practice in turns. when you can do that, then practice parking in tight spots. When you can master that, go back out on the busy streets.
p.s. it's spelled BRAKES. Fail!