Antenna connects to the converter box RF antenna input.
How you connect the converter box to the TV will depend on the connections that are available on both the box and TV.
First option is to use the RF output of the converter to the RF antenna input of the TV. The TV would be set to channel 3 or 4 usually.
Next option is if the converter box has AV outputs (3 RCA jacks) and the TV has AV inputs. This will give you a better picture than using the RF connection. You may not be able to switch the TV to the AV input without the original remote.