By default if we add user from useradd command without any option it will be added in home directory.
To change home directory of a user we can use usermod command.
Lets try see an example to change user (test) home form /home to /home1.
Run following command to modify:
$ usermod -d /home1/test -m test
Now open /etc/passwd file and search for test user where you can see home directory as /home1/test, previously it should be /home/test.
You might mention that this moves the existing directory over to the new one. Users may not want that to happen. If so, eliminate the -m option.