If you are considering graduate school, it is essential that you talk to people with experience in your chosen field. With PhD programs, everything is field specific. Some programs, like public policy, will take undergraduates from a variety of backgrounds, while many STEM fields will only take undergraduates from very specific concentrations and will want applicants to have started independent research by the summer after sophomore year. Most of your resident and non-resident tutors in the House are current graduate students and can be a great resource. They can help you with the application process, choice of institution, and with general wisdom and advice on your field of interest. In addition, many members of our Senior Common Room are faculty members and administrators at the university and would be valuable resources.
The Leverett Pre-Graduate and Research Committee is comprised of resident tutors who provide advising for making decisions about grad school and undergraduate research. They can also help you set up mentoring relationships. Contact RT Joshua Lansford for any questions at email@example.com.
Another valuable resource at Harvard is the Office of Career Services at https://ocs.fas.harvard.edu/ma-phd-arts-sciences.