Troubleshooting any engine that doesn't crank starts with checking the batteries. If the car jumpstarts when connected to a working engine, the battery likely needs to be replaced. Next, the starter engine should be inspected to ensure that it provides sufficient torque.
If the engine cranks but doesn't start, the battery might not have sufficient power to get the engine turning. Again, attempting to jumpstart the engine can help. Self-contained batteries designed to jumpstart cars can help get the car running before the replacement battery is installed.
If the battery seems to work but the engine still doesn't start or shuts off intermittently, the fuel line or fuel injector might be clogged or otherwise damaged. In general, poor fuel delivery doesn't cause the engine to overheat but might lead to smoke building in the car. Problems with fuel delivery often require expert help.
Engines that start but overheat are difficult to troubleshoot without professional tools and a thorough investigation, but it's worth filling the engine with coolant to see how it responds. If the coolant bubbles out of the engine, the problem might lie in the water pump or a blown gasket head. If the engine runs for a while but later overheats, there might be a leak in the coolant.