If you're doing real time with menus; the easiest/simplest way would be to have the ability spawn a prefab of the projectile, use the event system to make a battle event animation to change the position of the prefab to the target; and have a Damage Dealer on the prefab projectile.
Doesn't really matter if it's activated by menu commands or inputs - the way to go is with damage dealers/zones and spawning/moving the projectile prefab in the event
Please consider rating/reviewing my products on the Asset Store (hopefully positively), as that helps tremendously with getting found. If you're enjoying my products, updates and support, please consider supporting me on patreon.com!
---------------------------------------
Personal Twitter: https://twitter.com/AMO_Crate
I make RFI! https://twitter.com/NootboxGames
If you're enjoying my products, updates and support, please consider supporting me on patreon.com!