If your TV has a built in digital tuner then you will have an antenna input for the coax cable.
The USB is for powering the antenna so you can plug it into an unused USB port on the TV or use an external power supply.
The TV manual will tell you how to run a channel scan which you will have to do before receiving any ova channels.
If the antenna is directional it may pick up more channels in a different location or orientation. You have to rescan if you move the antenna to find out if you have more channels or less.