Most ATSC digital converters work with most antennas and all TV's. Some let you use the converter's remote to also control the TV, others have a remote that controls only the converter and change the channels, and you need the TV's remote also. You leave an old TV on channel 3 or channel 4, sometimes you can choose which.
Whether you use a converter with your old TV or buy a new TV that does not need a converter, reception will average the same. Usually you need a better antenna than what you used before this digital craze took over.========
If your antenna lead in wire or cord has two loose end bare wires or two lugs, you screw these lugs onto a little adapter perhaps the size of your thumb and the adapter plugs onto the back of the converter box or a TV with built in digital tuning. If the TV antenna input has nothing but two screws, you take the round screw on cable and screw that onto a little adapter that may look like an extra fat cigarette and there are two wires that come out the other end to screw onto the TV antenna input. Don't throw these little pieces away if you have to throw out a dead converter box or VCR. These little gizmos can be purchased separately at a TV store.