DO I NEED A NEW ENGINE OR ECM? How can I test it somehow to know for sure sure?

What is your question?

I got ran off the road into a small ditch, it didnt cause me to have to stop or check my car. It drove approximately 60 miles that day. The next day I got approximately 25-35 miles and then it started smoking and kicked or jerked then died. It started back up but only for just a moment. I cannot remember if it made a pop sound or bang. I have been asked that question before in regards to this. When I try to turn it on the fuel pump does come on. But that's all. Could it possibly be ANYTHING else other than the engine? Is there a way to test something, or do something or some kind of mechanics " trick " as my uncle would say. And maybe to be able to find out or diagnose the ACTUAL and ACCURATE cause or issue? I have been reading and studying on this for 2 yrs. I dont want to junk it, because its just idiotic to do so, even if it was the engine, the car itself is perfect inside and out, no wrecks, paid off, and you can get a new engine for as little as FREE-$375 depending on who you know. Some people however would pay $1500 or so by taking it to a shop and having to pay there price for a new engine. Anyway, its worth more than $100-$200 to me. So while I have had so much time to just read about it, since I have not been able to come up with $375, what a salvage yard has a new engine for, I read that it may be the computer module. Or ECM? Or eccetera. Is this true? How can I find out? Please can you help me? I thank you more than ever, so very much. Thank you.