My car is stuck is stuck in idol it wont go in to gear it just grinds

I an assuming that since it grinds that this is a standard shift transmission. If so, your slave or master cylinder for your clutch has either failed or leaked out, or both. Try adding some brake fluid to your Clutch master cylinder and pump vigorously to purge any bubbles. If you can engage your transmission after this, you will need to have the hydraulic clutch system bled. Until that time you will need to pump several times between gear changes to use the vehicle.