I have a Kenwood tk-790 and was wondering if it could be programmed to be a ham radio to pick up the normal cb channels.
OK, North Carolina,
So that puts you under the Federal Communications Commission.
There are not any frequencies you can use that radio on that do not require an FCC license.
About the best you can do is to get your amateur radio license.
The TK-790 comes in a few models, frequencies are 148-174MHz or theres a 136-156MHz version. Ideally you'd want the 136-156 so you can use it on the 2 meter amateur radio band (144-148MHz), although I believe it's possible to trick the higher split model into working lower.
It will not receive on the CB radio band, it's physically not capable to make it work on those frequencies (26-27MHz).
So, a couple of options….
Sell the radio and use the proceeds to buy a CB radio of your choosing. That'll get you something legal that you can use on the CB bands.
or.
Get your amateur radio license and find someone to program the radio with amateur radio frequencies. The technician class license isn't hard to get, but finding someone to program the radio might be a challenge.