Let’s say you’re standing 1 meter away from a door and you want to walk to the door.
But before you arrive at the door, you must reach the halfway point. But to get to the halfway point you must first reach the quarterway point. And so on, ad infinitum.
So to travel to the door you must travel these distances: ½ meter, ¼ meter, 1/8 meter, 1/16 meter, 1/32 meter, 1/64 meter etc etc.
So Zeno argues that because the sequence goes on forever, you must cover an infinite number of finite distances (*).
Meaning of course that you will never get anywhere.
Bit like Jakarta really.
(*) The paradox wasn’t exactly solved but a more streetwise fellow than Zeno simply got up and strode the 1 meter to the door before rubbishing the abilities of the erstwhile Greek philosopher.