P0304 error and shifting problems

What to pass somebody in my 2007 Silverado
when I got a flashing check engine light. A loss of
power and shaking an idol took it to o'reillys they
read it as a P0304 error code Which is a cylinder 4
missfire. I am also having problems shifting into
2nd  From 1st . The truck likes to lurch forward. I
changed out the coil pack on cylinder 4 and it did
nothing so I checked the rest of the Coil packs.
Same result so now I'm trying to weed out why the
engine is shaking and what could possibly be
causing my shifting problem. I'm curious if I have 2
separate problems or if it could be a fuel air ratio
problem that's causing my shifting to act up