Hey dude, I know lemmy is generally pretty anti AI (for various good reasons) but having read your other replies on this post, since you said you don't know what help you need;

I think there are probably only two things which might help you quickly (since you seem to be in a hurry, understandably so if it's your only computer):

1. find someone experienced with Linux who's willing to get on a phone call with you and talk things through, diagnose and guide you step by step till you have a usable system again. I might be willing to be that person if you're desperate and can't find anyone else, I'm free ish for the next few hours.
2. use another device with a camera (eg smartphone) to access one of the multi modal llms eg Gemini, ChatGPT, Claude etc and get help from the LLM, with you describing everything you did so far as best as you can and what symptoms you're seeing now, potentially sharing photos of what your hardware is and what you see etc. Follow things step by step and ask it to explain things as you go, try to learn throughout the process rather than just running things blindly.

Good luck! Try not to be put off by this experience, use it as an opportunity to learn more about how your tech works and help yourself be more prepared for recovery in future (eg always have a bootable Linux usb stick ready to hand)🙏