Forscan will speak to the car and program keys, but you need at least 1 key to get into it in the first place.
The chip in the key if its a Ford badged one looks like this - your best bet is to try and find it and confirm if it is in the key (should be located inside the horseshoe shaped bit where the fob sits) and if not try to find it.
https://www.ebay.co.uk/itm/Ford-Galaxy-2000-2006-ID44-T15-PCF-7935-NXP-Transponder-Chip-PCF7935AS-UK/122870799935The petrol ones will not crank if the chip isn't detected (and it has to be one programmed to the car), you seem to be getting further than that. It could be a relay 109 type problem, I found that would stop you getting into the diagnostics, but would be particularly unlucky if it was. If it is that then someone handy with a soldering iron should be able to sort it, otherwise replace the relay.
I take it this is the only key to the car? If so and the chip can't be found, it will be a case of getting a locksmith that can sort it to do so (would be a good idea to get a second key cut at the same time if possible). If you have another key that does work then forscan will allow you to add another chip as long as you get a preprogramed one (the one I've linked to above is suitable, as I've used two of those to add to mine after someone borrowed it and managed to lose my original key, you can't clone these ones like some others can be, they have to be programed).
