By default the Ubuntu package management installs all applications for all users.
This will not stop you from manually installing additional applications to a user's HOME directory. In this case you will have to copy this installation over to the other user's HOME.
Most applications will store user defined settings in a user's HOME. Most but depending on the application not all setting may also just be copied over to a new account to make them identical.
A special case are virtual machine's hard drives or Wine bottles that will be stored in a user's HOME by default. To use these from all accounts we can either make a copy resp. clone them to the other account, or we make sure we store these in a shared directory accessible to multiple users.