You can`t be that bad after 7 lessons,I would ask why and if you don`t get a satisfactory answer change your instructor.My sister was being fobbed off by her instructor about her test, changed and passed after 4 lessons. I think some of them string it along to make money out of you.
I was taken on to a main road at the end of my first lesson and then by my third lesson i was on busy roads. Do you feel confident and in control of the car on your lessons? If so you should definately be trying bigger busier roads, ask your instructor what they think of your performance so far and if they will let you try busier roads if your not happy change instructors
This all depends on the instructor / school that you're with.
I went onto the main roads on my first lesson and that was with a local school.
I know for a fact that British School of Motoring (BSM) actually stick you in a driving simulator for a couple of lessons before actually putting you in a car.
This might sound good to some people, but it's not actually a simulator but instead you're just sat at a normal computer with a steering wheel plugged in and left on your own.