All Business Central object development work starts from within Visual Studio Code in the EXPLORER. After opening a project folder, you should be able to see the following screen:
The type of object that we'll be working on is chosen by the object definition, which we can view by clicking on one of the files in the menus, as shown in the following screenshot:
It is considered a best practice to apply logical naming to your files so that you can see which object type and ID is used without having to open each individual file.