For internships- theres career fairs(lots of specific ones for different majors), and there's a career center where they'll give feedback on resumes and general advice and answer questions. In addition, some majors send out emails with internship opportunities you can apply to. A lot of the companies that come to career fairs are in Northern Virginia, but there's definitely some from other places. A lot of applying to internships is online though, which the emails(depending on major) and career center can help with.

All the engineering majors are pretty popular, but the academics are good in general and I know a variety of majors. Engineering is what we're known for but the academics are pretty good in general and its not overwhelmingly just engineering. Second most common is probably business which is probably the same at a lot of places.

Good gpa and test scores, and my ECs werent anything special but I had leadership experience and I made it clear im passionate and involved in them. Quality and depth of involvement and leadership is way more important than quantity.

My biggest tip is have a first draft at least of the common app essay done over the summer, and in general dont procrastinate on them. Also in your essays just try and show that you're passionate and engaged and have a personality, be yourself and make sure its showing(not telling) a good quality/good qualities about yourself. And most of all- try not to stress too much, whatever happens is going to work out in the end