[HELP] Launch Arrow


I am working on a new game on mobile, I am a bit confused on how to tackle this problem,

I am looking to make an arrow appear when i press on the screen and be able to select a direction on the z axis to then be able to launch my character in the direction of the arrow.
I am not a total beginner, I just need to understand how I could achieve this, but my brain is not working properly!

many thanks.