It could be there is a problem with the battery or starter relay as this can cause the car not start. You may have to replace these parts so as to have the problem solved as this is the best option. You can have a mechanic check it out to determine the real cause and have it fixed too.
There is two fuses on for starting and one for charging follow the positive wire back to a plastic black case take top off and look to see if fried if so change ten dollar fix. If not that your starter is bad change hundred to two hundred dollar fix. Good luck