*Update*
I contacted the ONN company by chat and they were wonderful in fixing my problem. They told me to go to:
Settings/TV input/Live TV/Antenna & Cable/ and scan channels and it worked!
I just got that TV yesterday, I plugged in the antenna cable, but no cable/antenna icon is showing and I cannot access certain channels such as 2, 44, and 59 for example. I am with Mohawk Networks, not showing on the list along with Directv etc.
The antenna/cable outlet is located in a different spot than my previous Roku TV (under).
I could watch these with my previous Roku TV. Antenna is located on the side.
Thanks for your help.