Host families rely entirely on luck. You must have good living habits, know each other's living habits and rely on your interpersonal skills. Host families are all off campus, and you have to solve the transportation problem to and from school every day. Many activities can't be attended because of traffic problems.
"Some people say that host families are not good. If they feel inappropriate after getting along, can they change it? Still live in the school dormitory. " Generally, if you are sure to leave, you can definitely leave, but 1) you may lose all or part of the advance payment, 2) you will waste a lot of time looking for a house and moving, 3) it is difficult for others to find a co-tenant, 4) you may not be able to enter the school dormitory until the beginning of the next semester/quarter, and 5) if you want to move to another place, you usually have to sign a lease for half a year or even one year.
"Some people say that host families are not good": Host families often have limited economic conditions. When the main purpose of host families is to supplement family income, their help to you is limited.
If you really want to experience the life of a family living in the United States, you'd better take advantage of the summer vacation, Christmas, Thanksgiving and other holidays in the United States to participate in short-term student activities, which sometimes include traveling to other cities and arranging students to live with local families. Such families are generally successful in the United States, with the purpose of helping students enrich their lives or strengthening exchanges with certain countries/regions. Hosting families must meet certain conditions before they can have boarding conditions. The host family is very good. Generally, it is completely free or nominally charges a registration fee far below the market price.