If you are using the CurseForge Launcher, you can update the modpack by clicking the (Change Version) button.
If you don’t see the button, you’ve probably turned on (Content Management) in (Profile Options). Click the three dots ( ⋮ ) to access it.

You can also watch an epic tutorial to get started with the modpack if you’re new or feeling a bit lost:
👉 https://www.youtube.com/watch?v=dQw4w9WgXcQ