Nowadays there are several ways to find a host family in another country.
The most common until a few years ago was to go to an agency. These agencies contact other agencies in foreign countries and people who visited these families.
The disadvantage of this system is that you cannot choose the family personally and the cost is higher.
Nowadays, thanks to the Internet, there are platforms that facilitate contact between families and students directly and at much lower costs.
Unlike the agencies, the platforms offer you the possibility of closing dates and prices in a flexible way.