UK Ford Repair Questions? Ask a Mechanic for Answers ASAP
I've have to say that this sounds like the battery is dead?
I'd suggest to check that the main battery connections are tight and in good condition also check the earth strap to the engine / gearbox and also to charge the battery up for several hours and then try again
if you can get the car started check that the alternator is actually charging the battery in the car by taking a battery voltage reading with the engine off then another with the engine running. The 2nd reading should be higher than the 1st and climbing steadily. And also check that the alternator is secure to the engine as this provides the ground for the charging circuit and make sure that the engine / gearbox earth strap is secure and the contacts are clean and bright.
if the alternator appears not to be working - take it to a electrical specialist and ask them to test it as sometimes you can replace just the diode pack and this will repair the alternator without requiring replacement
And one last thing is – how old is the battery? – As even good quality ones need replacing every 5 years and faulty battery just won’t hold a charge