My guess is that top 50 may be tough. However, there are a lot of very good universities that are likely to admit you given your strong up trend and very good grades for your junior and senior years, along with okay grades for your sophomore year. It is relatively common for students to mature and get their act together after their freshman year of high school, and sometimes significantly later.
Your budget is going to matter quite a bit.
Are there universities in your home country that would be a possibility? Would you want to consider other countries? As one example, universities in Canada would not care about your freshman year of high school at all.
You should be able to compute your unweighted GPA yourself. Just figure a 4 for any A, a 3 for any B, a 2 for any C, and so on. Then compute the average for each year. Admissions will look at your actual grades, but for the purposes of those of us here on CC just having some sense of your unweighted GPA would be helpful because weighted GPA is computed very differently at different high schools.
In terms of being on a visa, I am assuming that you mean a parent is on some form of temporary work visa. If you have a permanent resident visa, that is essentially the same as being a US citizen for the purposes of university admissions.