Loosing rpms and car shuts off

Start by checking codes and fuel pressure. This could be many things but report back after checking those two. Alex

try looking at the vacuum lines on the front left side of engine,one in particular is a 4" line in the shape of a horseshoe ,the 2.4l engine had constant problems with vacuum lines collapsing at idle causing it to stall very quickly after start-up

next step would be to hook up to scanner to look at fuel trims and other pids if it can idle long enough to read the data

Usually after ones auto repair savvy has reached its limit - it's time to make arrangements with a local auto repair facility to have the problem professionally diagnosed. I certainly understand that anyone would want to do the work themselves to try and save a buck or two - however if not careful - can easily wind up spending more on hit or miss diy parts replacement. ▪️https://repairpal.com/repair-shops▪️ Good luck with it!