ignition coils

He has bailed so now i am walking to work and trying to fix this myself.

Nothing got replaced when he saw what he was dealing with. He just removed one coil so i could get a picture, then he put it back. It had a Miss in the engine that you could feel when you were at a stop light or stop sign. So I took it to O'Reilly's and they put it on the computer and said that there was an engine Miss and that the spark plugs needed to be replaced. So I purchased wires and plugs only to find out that it doesn't have wires it has coils, and now they won't take the wires back cuz it's been over 30 days even though they are unused brand new in a box. My late husband used to take care of all this but since his death I can no longer afford to take it to a mechanic so I'm trying to do all this myself. Truly a bummer