2002 Audi TT Acceleration problems

The clutch experienced failure while on the highway and wouldn't go into gear without being put into neutral first then into second gear . Then while driving one day I couldn't put it in reverse it's just gone so now the car will roll slightly even with the emergency brake on but I was put in danger the day it wouldn't shift gears as it should while on the highway leaving me pretty much in fast motion but unable to continue in gear as it should which caused me to have to drift to the side of the road to then experience the effect of it being in neutral to second to continue driving however the vehicle seems to be high reviving in all gears after this experience happened

One morning started up the engine on my audi, and the engine sounded like it had rough idling, stuttering sound to it. I had took it for a test drive and experienced lack of power, hesitation in engine, rough idling, and then check engine light came on. Checked out the code. It came up to be (p0304) cylinder 4 misfire. I took it to a mechanic, and he replaced spark plugs, coil packs. The problem still existed. He had checked the compression. It was good. Check all wires, senors...Ect. Anything he could think of and...