I have looked into this several times over the years but not recently.

Boat and RV suppliers and truckstops sell 12V TVs, etc. They are costly.

Buy an inverter that has some support. A truckstop inverter has no support. If you go the inverter route, read about sine wave inverters.

We have an HP entertainment laptop with a tuner card. I bought it in early 2007, I think. It brought me into the digital TV era. I could tune into digital stations over the air with the laptop, tuner card and an antenna. Works for DVDs, cable, satellite, and internet TV. Came with a couple remote controls, one just like a home entertainment remote and a small one like for a car stereo. The PC is also great for internet at coffee shops, etc. Last time I looked to replace this laptop the offerings were pretty slim.

Most, almost all, digital TV is broadcast in UHF, select antenna accordingly. I eventually will build an antenna based on fractals but it's not a high priority. Find info on the web.

In most locations you can get a lot more stations if you can aim the antenna. TVfool.com and antennaweb.org are two good sites for info.