Use Box with Numbers on Mac
You can collaborate on Numbers spreadsheets stored in Box. Just like when you’re collaborating on a spreadsheet stored in iCloud Drive, everyone can work in real time and see changes as they’re made. When spreadsheets are stored in Box, you need to use the Box controls to set sharing options or stop sharing.
For instructions on previewing, editing, and creating Numbers spreadsheets while signed in to your Box account, see the Apple Support article on using iWork documents online in Box.