How can i add a tax option on expenses? i added a new 10% pst liquor tax in the TAXES category and it doesn't show up in sales tax options.

Hi there, 

Welcome to the Community. I'd be happy to help with adding and using a sales tax code. 

To make sure your new tax code shows up in the taxes drop-down, please follow these steps:

1.     From the left menu, select Taxes.
2.     Select Sales Tax at the top. (Tip: If you use payroll in QuickBooks Online, you may need to select Sales Tax as opposed to Payroll Tax.)
3.     Select Manage sales tax.
4.     Locate the sales tax agency you wish to add the new rate for, and select Add custom rate.

If you've done it this way, I recommend clearing cache and cookies on your browser. Doing this will help fix most issues the site may be having. Here's an article that'll show you how to do that: 

https://community.intuit.com/articles/1771580

Give this a try and let me know how you make out.