Use the Candidate window with a Japanese input source on Mac
After you set up a Japanese input source, the Candidate window displays all of the candidates available for any kana text you enter (based on words in available Japanese dictionaries). You choose the character or characters to use in your document from the Candidate window. If you set the preference for predictive candidates, the Candidate window shows the most likely candidates to complete your text as you type it, based on what you previously typed and selected.
Note: Typing suggestions that display in the Candidate window also appear in the Touch Bar (if your Mac has one).
Enter characters from the Candidate window
On your Mac, switch to a Japanese input source.
In an app, enter Japanese text to display the Candidate window, then do any of the following:
Press the number that corresponds to the candidate you want to use.
Double-click the candidate you want to use, then press Return.
Press the Down Arrow key, the Up Arrow key, the Space bar, or Shift-Space bar to select a candidate.
Press the Right Arrow key or Left Arrow key to select the next or previous portion of a text string.
Press Shift-Right Arrow or Shift-Left Arrow to expand a portion of a text string.
After you choose the character or characters from the Candidate window, entering the kana again will display the candidate you chose as the first option.
Navigate in the Candidate window
On your Mac, switch to a Japanese input source.
In an app, enter Japanese text to display the Candidate window, then do any of the following:
Change how candidates are organized: Click the tabs at the bottom of the Candidate window or press the Tab key.
Scan through candidates: Use the scroll bar.
Scroll up through candidates a page at a time: Press and hold the Shift key and press the Up Arrow key, press Control-R, or press the Page Up key.
Scroll down through candidates a page at a time: Press and hold the Shift key and press the Down Arrow key, press Control-V, or press the Page Down key.
Get more information about a candidate: Select it in the Candidate window. If more information is available, a book icon appears next to the candidate and the information appears next to the Candidate window.
Change the font used in the Candidate window
Some symbols can be displayed using only certain fonts, so you may need to change the font to make sure symbols are displayed correctly.
Characters in documents are displayed using the font set by the app. If the app uses a different font than the Candidate window, you might see a different symbol in your document than the one shown in the Candidate window.
On your Mac, switch to a Japanese input source.
Click the Input menu in the menu bar, then choose Open Japanese - Kana Preferences or Open Japanese - Romaji Preferences.
Choose a font and font size for the Candidate window.
If a rectangle is displayed instead of the symbol you want, the symbol may not be available in the font you selected.
Tip: To change the highlight color of the Candidate window, choose Apple menu 
, then click the “Highlight color” pop-up menu and choose a color.