i want this zombie to shoot arrows when im far from him

[chocolatemlk]

on rightclick with nether star:
    name of player's tool is "&5&lBoss Summoner"
    remove 1 of player's held item from player
    spawn 1 of zombie at location of player
    equip last spawned zombie with diamond chestplate of protection 10
    equip last spawned zombie with diamond leggings of protection 10
    equip last spawned zombie with diamond boots of protection 10
    set last spawned zombie's held item to iron sword of sharpness 100
    set last spawned zombie's held item to bow of infinity 1
    set last spawned zombie's item to arrow
    set last spawned zombie's max health to 1000
    set last spawned zombie's health to 1000
    set display name of last spawned zombie to "&6&l&nZombie Knight"

command bossstar:
    permission: op
    trigger:
        give player 1 of nether star named "&5&lBoss Summoner"
on death:
    if display name of victim is "&6&l&nZombie Knight":
        cancel drops
        give attacker 1 of Mangrove propagule