Microsoft Designer Bluetooth Desktop, Wireless Keyboard & Mouse Set
If you cannot connect your keyboard and mouse to your desktop PC, that means your motherboard does not come with built in bluetooth. To solve this problem, You need a bluetooth adapter.
ASUS USB-BT400 Bluetooth 4.0 USB Adapter
Tech Predator PCs
I can connect to internet using a wired cable, but I cannot connect to wireless WIFI. This means your PC does not have built in WIFI, you need a WIFI adapter.
ASUS USB-N53 Dual Band 2.4GHZ 5GHZ Wireless N USB Adapter