By default CentOS Ships with CLI. We need to install the GUI in a manual way. It's way easier than you think.
Follow the below steps for installing GUI in CentOS
By Default you'll be in CLI mode.
Login First, Then run these command one by one.
su - root
Give Password and Press Enter. This command will switch to root user. Because not like Ubuntu we can't directly install packages by sudo command. Every time we need to be root.
Then Run this command.
yum install epel-release -y
This will configure the EPEL Repository which we need to install packages from.
Next. We need to install Server with GUI package. But default it'll install GNOME.
yum group install "Server with GUI" -y
It'll download all the required packages. Once the Download and Installation is complete.
Run this command to set GUI as default.
systemctl set-default graphical.target
It's time for reboot.
This time you'll see beautiful GUI.