How to type "Full Width" characters?
• Open system preferences

• Select ‘Keyboard’

• Go to the ‘Input sources’ tab

• Click on the plus button at the bottom to add a keyboard format

• Select a keyboard format that supports full-width text (e.g. Japanese)

• Make sure that the full-width input mode is enabled. (For the Japanese keyboard menu you will need to tick the box next to ‘Full-width Romaji’)

• Make sure that the ‘Show Input menu in menu bar’ box is ticked

• Select the full-width mode in the menu bar

• You should then be able to type in full-width text

Screenshots:
https://imgur.com/a/eHqyl