@ucbalumnus gave you the link for the NAAB listing above. There’s only about 50 B.Arch programs in the country. While it’s semi-limiting, it helps you narrow down your options really quickly once you put in budget, geographic preference, school size, etc etc etc…
While it might not be the case for every school on the list, expect that for many of them the BArch program is likely far more competitive to get into than the broader school numbers might suggest.
You’ll want to look at the admissions criteria for your narrowed down list to understand if a portfolio is required (and what the criteria of the portfolio for that school is - they will differ from school to school). Not all schools require a portfolio and for some it’s optional. For the optional they’ll mostly tell you “it can only help”.