My business does not apply for gst, how do i reset the setting so i dont see bas?

Welcome to the Community, @usersheltonrosario9.

As an insight, we are unable to turn off the GST once it's turned on. However, if your QBO account is under 90 days old, you can reset your file and start again. This process is called purging. Here's how: 

1. Log in to your QuickBooks Online Company.
2. Change the URL to include /purgecompany. Example: Change https://sg.qbo.intuit.com/app/homepage to https://sg.qbo.intuit.com/app/purgecompany
3. Then, type YES to delete the data, then select OK.

If your file is older than 90 days or you do not wish to reset your file you can change your default tax rate to Out of Scope. Here's how: 

1. Go to the Gear icon, then select Account and Settings.
2. Select the Advanced tab and go to Accounting section.
3. Select Out of scope of GST in the Default tax rate selection field, then click Save and Done. 

For future reference, read through this article: Remove a GST rate. It helps you learn about removing a tax rate that you created in QuickBooks. 

Feel free to ask more questions here in the Community. I'll be here to help some more.