Heat seeking bullet entity

Hi everybody! I’m making a mod for Minecraft. (Why slaw would I be using Mcreator?) and I wanted to make a mob that acts as a shulker bullet. Problems I’m having:

• how do I make it so a mob egg doesn’t appear in the GUI?

- how exactly do I make a flying mob that acts as a shulker bullet?

- the mob is a ghost: I want it to possess the player. (Force the player to drop their item and then walk in a random pattern)

thanks in advance! :)