Hiya,
I really feel for you - I was in a similar situation. I ended up taking a year out after my GCSE’s . I was put on antidepressants because my mood was so low.
I think the most important thing right now is to focus on yourself and try and look at the future positively (I know this is so hard right now, but this feeling is only temporary)
As I was beginning to feel better, I took chances and applied to every 6th form and college in my area, I sent personal emails to every individual place explaining my situation but how motivated etc I was. I actually got a response from all my emails - all asking me to come in so I could look at the school/college etc. Even if you get offered to retake your GCSE’s at college then it’s a step forward, and they will explain how you can develop further etc afterwards.
I’m now at the end of my a levels, and have 2 unconditional offers despite this - I would have never of even thought this had happened 2 years ago - I was so down and didn’t even want to go back to school
I hope this helps - good luck ❤️