So which one of the ten / tamten / tamhleten or tento / tenhle does tehle come from?
HLE is an archaic word for LOOK! If we strech it, tenhle means .this look!.
Try to search the forum first, it has been discussed before.
Here you can use both. člověk is closer to a (hu)man, osoba is closer to a person, but there are large overlaps.