I installed Bookworm Lite on my Raspberry Pi but then thought it would be nice to install the GUI.
First make sure you update the Pi:
sudo apt-get upgrade
sudo apt-get update
sudo apt install xserver-xorg raspberrypi-ui-mods
There will be quite a lot of packages to install.
Say Yes and the installation with proceed.
If you would like to set the Pi to boot into the GUI, or not, run:
sudo raspi-config
System Options > Boot
Here you can choose:
B1 - Console Text Console B2 - Desktop Desktop GUI