It’s there (if the TV is relatively new.). Where it would be in the menu is dependent on your TV model.
I would do a search on “Change Resolution Settings for Brand Model”. That will probably bring up your user manual. You might even find a You Tube video.
Are you using a digital TV antenna?
All antennae are analog.
It really isn’t an antenna problem. This whole ‘digital TV antenna’ thing is really just a misnomer/misinformation.
What matters on the TV antenna is bandwidth and directivity (gain that includes efficiency of the antenna and downlink losses.).
I have a regular old HD yagi/uda antenna in my attic that picks up HDTV signals from Atlanta 60 miles away quite easily. All it needed was an inline amp located at the antenna terminal outputs.
The problem sounds to me to be a resolution/setting problem on the TV rather than the antenna.
1. Yes, digital antenna
2. There’s no coax input on the tv, that’s why I’m using a converter box and hdmi. No other inputs except USB (which didn’t work).