How do i navigate RC car with a gps module on it from point A to point B?
GPS indoors is a terrible idea.  Your accuracy will be so poor, and being indoors implies you would need something fairly accurate because the scale of your setup will be relatively small.

Additionally, even if you used it outside, some form of dead-reckoning (e.g. compass) would be of enormous use so you could determine which direction you were pointed.  It would not strictly be essential, only if you wanted to approach this in an efficient manner.

Using some sort of filter with GPS is a good idea, but if you are indoors, the position it will provide will not simply be randomly distributed around the true position, but rather around some chaotic mix of positions of the nearest windows based on what satellites you can get a fix on.