I'm currently studying IT computer systems at school and we have to make a database enabling us to do multiple things, I've heard that an interface is program which will enter multiple things at once - how can I make one? Or get one?

We don't do peoples homework here though we will still help you if you ask specific questions.

An interface is simply what you see on the screen in order to edit/view data in the database.

It all depends on what type of database software you are using. Are you using MS SQL Server, My SQL, MS Access, Oracle, or some other software?