This is one of the most asked questions.
https://forum.kicad.info/search?q=Pin%20connected%20to%20some%20others%20pins%20but%20no%20pin%20to%20drive%20it
And it has it’s own entry in the FAQ section:
What do you mean with “pin properties” (and where)?
The most generic answer is to first load a schematic symbol in the symbol editor, then hover over a pin and press e for edit.
But you have to be aware that KiCad’s own libraries are read-only so you can not copy them directly and have to learn to do some library management first.