You may not find a job when you come out of college, but you said that your parents are in business and there should be no problem with work. Now the social diploma is the first. If there is no college diploma, even doing business is a drop in the bucket. I have seen this before. Our school had it in previous sessions. We don't have the college entrance examination to do business, and there are sports cars at the class reunion, but we don't speak the same language as others. University is a necessary process in life. If you can, try it.
I think it's better for you to go back to senior two. 18 years old, sophomore year, graduated at 24 years old. What do you mean, too old? Have you no confidence in yourself? Then it's no use looking for students. If you cringe, nothing is possible. I graduated at the age of 24 and have more life experience than others. It may be more advantageous to find a job. You can think of it this way.
The content of the first year of high school is the same, and the second year of high school will be separated. Don't worry about not keeping up. If the status quo remains the same next year, it is not too late to find students again. You said that you want to study, which means that you are also very motivated. If you have the heart to do it, there is hope.
Also, don't say anything that you can't learn well. Be careful! You have a clear mind and an independent mind. I believe your ability is not bad.
Finally, I send you a famous saying from wuli cookie: learning is not the whole of life, but what is the meaning of life if you can't overcome even a part of life-learning?
Come on!