The Fyne project is split into many packages, each providing different types of functionality. They are as follows:

fyne.io/fyne/v2
This import provides the basic definitions common to all Fyne code
including data types and interfaces.
fyne.io/fyne/v2/app
The app package provides the APIs that start a new application.
Normally you only require app.New() or app.NewWithID().
fyne.io/fyne/v2/canvas
The canvas package provides all of the drawing APIs within Fyne.
The complete Fyne toolkit is made up of these primitive graphical types.
fyne.io/fyne/v2/container
The container package provides containers that are used to lay out and organise applications.
fyne.io/fyne/v2/data/binding
The binding package contains ways of binding data sources to widgets.
fyne.io/fyne/v2/data/validation
The validation package provides tooling for validating data inside widgets.
fyne.io/fyne/v2/dialog
The dialog package contains dialogs such as confirm, error and file save/open.
fyne.io/fyne/v2/layout
The layout package provides various layout implementations for use
with containers (discussed in a later tutorial).
fyne.io/fyne/v2/storage
The storage package provides storage access and management functionality.
fyne.io/fyne/v2/test
Applications can be tested more easily using the tools within the test
package.
fyne.io/fyne/v2/widget
Most graphical applications are created using a collection of widgets.
All the widgets and interactive elements within Fyne are in this package.