wordpress web site is hosted files + database data.
for the files u need 2 separate places to host them, lets say /siteone and /sitetwo, or whatever u want.
for the database u can have 2 databases.
there is also the prefix thing.
data stored in database in tables, each table have a name, and wordpress creates tables with prefix.
u can make use of this by making the prefix of first website something like one_ and two_ for second, that way u have 2 wordpress sites on same database with no interaction at all.
wish this help u, good luck.
