I cannot find language set up in my quickbooks online setting and I cannot get a help form QB assistant message.

Allow me to help you find the language setup of your QuickBooks Online (QBO) account, Aof.

At this time, language settings are only available on QBO international versions. If you have verified that you are using one, you can follow the steps below:

1. Log in to your QBO account.
2. Go to the Gear icon and select Accounts and Settings.
3. Select the Advanced tab and select Language.
4. From there, click the pencil icon and select the language you want.
5. Then, click Save, then Done to confirm the changes.

Our supported languages are Chinese, English, French, Italian, and Spanish.

In addition, I've added this article that can guide you in supervising your account: Help Articles for QuickBooks Online.

I'm just a post away in the comment section if you have other concerns about finding languages in QBO. Take care.