To use this option, you will need to click on the button Review files in order to choose one of the categories of files that you potentially want to get rid of (Documents, Recycle Bin, Applications…). The option Reduce clutter allows you to identify files too bulky, which take up a lot of space on your Macbook hard drive without you actually using them much. You will always be able to buy additional space on your iCloud account, in the event that it becomes full. In addition, iCloud allows you to store a good amount of documents and benefit from the application ICloud Keychain: your passwords are all saved.

You can also display your desktop and your documents on all your devices (tablets, phones, etc.).

You can now use iCloud, so you can access all of your videos and photos, whenever you need them.

Connect to your Apple ID to set up iCloud on your Macbook device.

Here is the procedure to follow to be able to use the iCloud storage option: By using iCloud, you leave free space on your Macbook hard drive, for other applications for example. You can use iCloud in order to store all your files (photos, audios, videos, films, Apple TV series….) and so that they do not take up space on your Macbook hard drive. Using iCloud to lighten Mac hard drive space

How to clean up mac hard drive space