Install the optional component
Complete the main Linux runtime setup first, then install Desktop & apps in DroidDeck to use the desktop and emulators. Plan for about 1.1 GB more storage beyond the roughly 3 GB runtime.
ARM64 Linux applications
The in-app Store installs ARM64 Linux apps and games from Flathub using Flatpak. The README also describes options for installing AppImages and setting up scripts.
The Store's Linux applications are separate from the GOG / Epic / Amazon library connections offered by Stores.
Desktop limitations
The official README says desktop compositing uses software rendering and that Firefox sandboxing is reduced under proot. Keep these documented limitations in mind when choosing desktop applications.
Installing a desktop component does not change the supported GPU list or establish performance for a particular app.