How to get full picture on CRT television sets

[uncleputz]

I must be the last guy on the planet to be able to figure out how to do this. I want to watch over-the-air, antenna TV on my old CRT television sets and get a full picture. I have read articles on this until my eyeballs bleed, still it doesn't sink in. The videos I watch use technical terms (VG97, rf modulator, etc) that don't make any sense to me. These items can't be purchased in a store, apparently, so they need to be scrounged. I don't know what I'm looking for. I have a converter box that I've had for ten years or so. Now I understand it may be "obsolete" and "HD 3.0" may have taken its place, so I may need a new one. No store either has one or knows what it is or what I need. I've used my old converter and a VCR/DVD player for an RF modulator and that doesn't work. So, would any of you be good enough to straighten me out? In nice, SLOW, deliberate language, devoid of techno-babble. The specific devices I need, specific methods to connect them, that kind of thing. I reckon everybody has problems with certain details in this hobby, this one is mine. I got the TV working, but can't take this next step. Thanks in advance for your help.