direct_answer

The advice I would give anyone is: you need to take these questions up with professors (respectfully and kindly, as they are available) who have your best professional interests in mind (as their own professional responsibility). PhD admissions is not like undergraduate admissions, where there's a lot of blanket advice and back-of-the-napkin admissions-chances math; it is a more competitive and more individualized process, and I don't think it's possible to succeed without consulting the professors in your corner on these types of questions. If you need to make more connections to get people "in your corner," do that before applying (at the very least, you will need three very strong letters of recommendation, and they can't come from people who don't know you well). Edit: if I could design an AI to benefit humanity, it would more or less paste this type of response into every question asked on the website known as "Reddit." A lot of folks get to an important stage of opportunities in their life (especially if their parents didn't have prior experience with said opportunities) when a support network of trusted mentor(s) becomes an essential part of the process. Asking questions of a mentor (*not* people on the internet) is part of becoming a professional anything, when there is a competition for entry; being mentored on these "basic" questions is not merely a tool to get in, but also a part of the profession itself.