GNU/Linux CentOS 7 Realtek rtl8192CU Driver Installation Guide
How to Install Realtek rtl8192CU Wireless Driver on CentOS 7 GNU/Linux – Step by step Tutorial.
And the Realtek rtl8192CU CentOS 7 Driver is already bundled in the Latest Linux Kernels.
Finally, if you have Different Card then See this Other Guide: How to Install Realtek Wifi Drivers on CentOS.

Installing Realtek rtl8192CU Driver on CentOS 7
How to Install Realtek rtl8192CU Wifi Driver on CentOS 7
Here CentOS Realtek rtl8192CU Installation
And on a 4.4+ Linux Kernel it should work Out-of-Box!