Hello and welcome to JustAnswer!
When the cams are slightly out of time on a 2.4 it will cause a rough idle but it will run essentially ok while driving.
These can be tricky to put into time until you've done them successfully a few times.
Start by getting the cams the right side up and the marks close. Slide the belt over one cam or the other and clamp it with something like a clothespin.
Route the belt over the other cam. At this point you can make adjustments to line the marks up rotating the cams as necessary. When you believe you have it then clamp the belt to the second cam.
Back the crank up about a half tooth counterclockwise of the ***** *****ning up. Slide the belt under the crank and rotate the crank clockwise to engage the belt.
Turn carefully until the slack is gone between the crank, water pump
and intake cam.
Slide the belt over the tensioner and tension the belt.
REmove the clamps and turn the engine two revolutions clockwise, line up the mark on the crank sprocket remembering the mark is on the trailing edge of the tooth.
Lay a straight edge across the outer marks on the cams and see where the inner marks land. If you're in time they will be nearly straight across, the inner marks being very slightly above the straight edge.