One of the first things that you might notice when logging into a new CentOS 7 minimal installation is there is no ifconfig command.
You can use the "yum provides" command to figure out what packages provide certain commands or files you're used to using.
#yum provides ifconfig
The utility has been deprecated, but if you want to use it, just install net-tools.
#yum -y install net-tools
Alternatively, you can get and manipulate your IP address using the ip command:
#ip addr sh