Backing up MacBook Air

FWIW, Time Machine serves two purposes. One is to keep a current backup of your Mac in case something goes wrong and you need to recover. The other is to easily migrate your user account/s, apps, settings, etc. to a new machine. If you don't mind setting up a new machine from scratch, or are not worried about losing any of your data, then feel free not to use it.

VLHXCJK wrote:

Videos, Photos and documents are the only things that I see keeping. What other items would you suggest saving?

iCloud does not provide computer backup. Use an external drive then use Time Machine or just copy over the data you want to keep. Save all files you want to keep.

You can't back up everything to iCloud. See the link at the top of this page.