Hey,
First of all I'm sorry you're going through this. It sounds like English is a very significant stressor for you and that your anxieties around it are really hard to cope with. My advice here is going to be two-fold: Firstly - and most importantly - it's best if you can work on things to improve your wellbeing, secondly I'll talk about VCE English and the role that has.
I'm not going to tell you should have a positive attitude towards English or that you shouldn't care about failing year 12 - it makes sense for those things to matter to you and for you to have strong feelings about them. However, in your current mental state you have amplified these concerns to be equivalent to your life when your life is so much more valuable than this. Having a mental state like that is hard & draining & I wouldn't wish it on anyone so I hope that you please seek help. You can do things to promote protective factors for wellbeing like getting enough sleep & having a healthy diet but as I'm sure you known it's not exactly *eats 1 carrot* "wow thanks I'm cured". That's why I hope you reach out to other people who can help support you through this. Ideally, that would include a professional (which you may or may not be already seeing). It's also important to maintain other social connections and supports. I'm hardly a professional but feel free to pm me anytime & I'll listen and answer as best as I can.
Now, onto English. To pass English you don't need to do well you just need to show evidence to your teacher of meeting the learning outcomes. This is the case whether or not you're doing unscored. What you can do to provide evidence of meting the outcomes should be a discussion you have with your teacher if you are concerned this won't be evident in your SACs. Getting less than 25 isn't ideal but it doesn't mean you've failed. I have a friend who wrote 1 sentence on their English exam & got a study score of 3 in English. Good study score? No. Did they pass? Yes. Did they get an ATAR? Yes (this was a few years ago so I can't remember exactly but I'm pretty sure it was >50). Point is, you don't have to do well to pass. If English is going to be that distressing for you maybe focusing on passing rather than getting a good score will take some of the pressure off.
Best of luck & I hope the difficulties you're facing ease up soon.