I know some schools require it but I wasn’t sure about Harvard.
You are required to live on campus freshman year and pretty much all four years
https://www.harvard.edu/about-harvard/harvard-glance/student-life
If you want to be a commuter student you do not know what Harvard is all about.
According to your posting history you are a high school freshman. You are getting a bit ahead of yourself.
Additionally, you would be in for quite a shock for the rents in the area. 
I know someone who lived off campus senior year. Financial aid covered it. Two percent live off campus. There is also a coop house off the main campus(es).