Actually you normally do not record from a television set per se.
The antenna cable or the cable TV cable goes to the VCR first and the VCR chooses what it wants to record using its own built in tuner (you program the VCR). The VCR also passes on the broadcast signals unchanged to the TV for its built in tuner to choose from when the VCR's TV/VCR menu setting (all VCR's have this) is set to "TV".
If your TV set has a "video out" jack whose purpose is to daisy chain the selected channel to other TV sets say in a classroom, then you can record from the TV. For a conventional 20'th century VCR the video out jack generally has to be a "composite" video jack which is yellow in color and delivers standard defnintion quality. You also need to connect a pair of (red and white) audio cables to your VCR input jacks.
In the U.S. (and perhaps some other parts of the world) the broadcast standards have changed and older VCR's will not tune in the available stations. If your area was affected then another box (a converter box) has to go between the antenna cable and the VCR to allow reception. Depending on the converter box, what finally gets to the TV through the VCR may or may not be high definition. This change did not suddenly affect cable TV and satellite TV subscribers although as months go by, one by one the cable channels may be changed to a digital format. Then you may need to upgrade the cable box or satellite tuner box. Newer cable boxes may have separate outputs for older VCR's and for hi-def TV sets.