The basic structure of the antenna comes from a capacitor.
An antenna is a device for sending and receiving electromagnetic waves. A typical dipole antenna has the form of a wire with both ends cut off. The antenna uses these cut wires as a springboard to send current through space.
At first glance, it can be challenging to understand that current flows between conductors are separated from each other.
However, anyone who has learned Physics knows that passing an alternating current through a capacitor causes a current to flow. Capacitors are two thin plates placed apart from each other. Even though the two electrodes of the capacitor are separated from each other, an electric field is formed between the electrodes, allowing current flow.
Usually, the electric field formed in the capacitor does not leak out to the outside. The antenna is a device to leak this electric field to the outside actively. The electric field leaking to the outside is called a radio wave or electromagnetic wave, and it spreads through space at the speed of light.