A few things that aren't clear from your post.

- Do you have a degree? If so, which subject

- You claimed you sent in over a thousand job applications and zero offers. What kind of jobs are you applying for? How far along in the process do you get?

I think your problem can be broken down into two parts: getting an interview and performing well in the interview. The first part is trickier IMO because its kind of a black box, although I managed to get contacted by big tech without a CS degree. The second part doesn't take years, it takes months of just cramming leetcode interviews. It's no secret what they look for and ask. They want you to do well and give you all the tools to do well. It's just putting in the effort by grinding leetcode an hour or two a day for a month or two.