On the Review tab, click Spelling & Grammar. If Word finds a potential error, the Spelling and the Grammar dialog box will open the spelling errors will be shown as red text, and the grammatical errors will be shown as green text. To fix an error, do one of the following:
Type the correction in the box and then click Change.

Select Review > Spelling & Grammar or press F7. In the Editor pane, select the correct spelling from the list of suggestions. Select Change All to fix every time this word appears in your file.

By following these steps Check your spelling and punctuation.
1. Open a Google Docs document.
2. Click Spell Check in the upper left corner. In the upper right corner, a box will appear. Click Change to use a suggestion. Click Ignore to dismiss a proposal. Click More to accept or reject all suggestions. Accept or ignore anything.