Fiesta mk7 want turn on at all and alarm wont disabled

[Thanos]

Hi I'm really hoping to get help her I'm about ready to set the car alight. I have a mk7 fiesta st and 4 days ago car was driving and working perfect the very next morning it wouldn't even switch on then thought my battery had completely died as the battery light was on for a few days. Just wanted to wait for all the places to open after the festive season. After replacing the batter same issue nothing. Thought maybe the key fob battery had died and replaced that and still nothing. I went online and found nothing. Even when I put the key fob up to the sensor on the steering wrack all it would do was put the air-conditioning on. I have no display coming up on the hud my cluster doesn't even turn on at all. Iv gone through all the fuses and checked those there all fine also my alarm is going of and will not disable at all now. Any advice would help.