Like ability to install different desktop enviroment?
Technically, with root access, yeah. It's just that Android's UI isn't a DE/WM in the desktop Linux sense
You can also just install different apps that change the home screen. Android calls them "launchers". You can install one from the Google Play Store or elsewhere like any other app. Then just set it up. Once it's setup, the phone simply loads that app's launcher instead of the phone's default launcher (which is usually also an app).