Grapple gun help

Hi, Im still a beginner at this coding within unity and I was wondering if I could have some help to make a grapple gun. So I press the q key and the player flies toward the connected wall and then when I release the q key the player will release the hook and start to drop.
I know this is an unreasonable request but all help will be highly appreciated.

Here are three things that might help you get started