2001 pontiac grandam se 2.4l twincam cranks over attempts to start but no go.

I replaced sparkplugs with new and new plug boots and oil change and new and new timing chain and cassette guides and tenstioner and fuelpump new ran for a month then it was saying misfire po300 so replaced the coil top with new then runned then 2 miles was running like Garbage then stalled out and retarted it when it was backfiring ran like Garbage again looked under car cat was cherry red replaced that now it wont run at all just cranks over wanting like it wants to run but not enough to keep it running.