Dear @Charles Young
To have Microsoft Word automatically check spelling as you type, you can enable the built‑in proofing feature by following these steps:
- Open Word and go to File > Options > Proofing. Under the section “When correcting spelling and grammar in Word,” make sure the option “Check spelling as you type” is selected.
- You can also enable “Mark grammar errors as you type” if you want grammar suggestions as well. After that, click OK to save the settings.
- Once enabled, Word will automatically highlight misspelled words with a red underline and grammar issues with blue or green underlines while you type, allowing you to right‑click the word to see suggested corrections. For reference: In Microsoft Word how is SpellCheck turned on

Next, ensure the correct language is set for your document. You can go to Review tab, then find Language, then choose Set Proofing Language
Select your language and make sure "Do not check spelling or grammar" is NOT checked > After applying changes, restart Word to ensure settings take effect.

Moreover, you can also use Editor (Home > Editor) to analyze your document and offer suggestions for spelling, grammar, and stylistic issues, like making sentences more concise, choosing simpler words, or writing with more formality. For reference: Check grammar, spelling, and more in Word

If spell check still doesn’t work, you could try to repair the Microsoft 365 app to see if the issue persists. After repairing Office, repeat the steps above to ensure Spell Check is enabled again. You could refer to this article: Repair an Office application - Microsoft Support
I hope the information shared helps point you in the right direction. Please try the steps above and let me know if they work. If not, we can continue working together to narrow this down.
The first response may not always resolve the issue right away, but with your help and more details, we can work toward a solution.
Thank you for your patience and understanding. I'm looking forward to your reply.
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