Goodman furnace
Everything seems to start OK but flame starts / then ends but
Furnace won't blow or even start to blow
Red light flashes 4 times indicates bad hi limit switch
Can the hi limit switch cause fan not to come on?
Or is the fan not coming on and causing the high limit switch to go into error.

The limit is doing it's job. It is shutting down the burners because of an overheat condition caused by the fan not coming on. Do you have a volt meter & know how to use it?

No but I can get one. Yes I have a basic idea how to use it.

You heat to measure voltage from the fan heating speed terminal on the circuit board to neutral. If you get +/- 120 volts, we know the fan is getting power. This measurement should be made 30-60 seconds after the burners fire but before the flames go out. If you do not get the voltage, most likely the board is bad.
If you do get the voltage, check the fan to see if it is seized. If not, you either have an open winding on the motor or a bad capacitor.

Does this furnace vent via a PVC pipe to the outside? If so check the pipe for obstructions