Hey there, @gurl94!
Ryder here, from the Social Care Team at Shopify. Thanks for posting! Taxes ultimately depend on the region you live in, as every country and state/province will have different tax regulations.
We're not able to support information regarding taxes, as we aren't tax experts. That being said, I was able to locate a Singapore guide for Income Tax you may be interested in reading through here. If you're still struggling, we recommend reaching out to a tax expert in your area as they'll have the best understanding of the local tax regulations and can advise you accordingly. Once you have a better understanding of how taxes are charged in Singapore, you can set them up in your Admin by going to Settings > Taxes. You can reference our Taxes guide to help you set them up.
Sorry that we couldn't be of more assistance! If you have any questions about how to set them up once you have a clear understanding of your tax regulations, let me know. I'd be happy to see how I can assist with the setup.