How to add a bossbar

[ImOnFireeeeeeeee]

command /spawnboss:
trigger:
spawn giant at player's location

how do i give this a bossbar?

 

[TheCubPlays]

Hello, you need to create a bossbar with an id for all the players like this:

command /spawnboss:
    trigger:
        spawn giant at player's location
        set {_b} to last spawned entity
        set {_h} to {_b}'s health
        while {_b} is alive:
            set {_remainingh} to {_b}'s health
            set {_progress} to {_remainingh} / {_h} * 100
            create bossbar titled "Boss" and id "Boss" for all players with progress {_progress}
            wait 1 second
            remove bossbar "Boss"

Btw I don't know if you wanted to make it so that the bossbar displays the boss's health too or not so I added that anyways, if you don't want it to display the boss's health on the bossbar just remove line 5,7,8 and the "with progress {_progress}" part.

command /spawnboss:
trigger:
spawn giant at player's location

how do i give this a bossbar?