Once you install a flavour that uses a specific desktop environment, can you change the desktop?
I installed lubuntu on my computer, but I want to use the unity desktop. I installed it with
sudo apt-get install ubuntu-desktop^
and deleted lubuntu-desktop, but when I restarted it seemed to reinstall the lubuntu desktop. Sorry if this question is silly, I'm new to Ubuntu.
Yes you can. But, while logging in, go to the top right (actually not exactly at the corner), and you will see a small icon to change the desktop environment you need to boot into. Click on it and choose the Unity desktop. (See the 4th icon from the top right in the image)
Mind you that installing another desktop is not very efficient and will cause issues like out of place icons, theme issues etc. although most of the things will work fine. So, if you are testing out Unity, its alright. But, if you want to continue with Unity, I suggest you install Ubuntu with Unity desktop again. Even if you do not, its okay. Things will run fine.
On the page where you sign in, with your username and password, you can choose, at the top, which desktop starts.