Hi, @MsWishywashy !
Katy here from Shopify. I hope all is well with you and welcome to our Community here!
Great question! With your monthly invoice, whether you will be charged tax on this, and how much tax you will be charged depends on your own location. If your business is located in a Canadian or American jurisdiction where Shopify has a business presence, then in these cases Shopify is required by law to charge applicable taxes on your subscription. We have some more detailed info on this here to help clarify this further. If you are not seeing this on your own invoice(s) it is then likely that you are outside of one of these locations. Do however feel free to let me know if there has been an error, and I will be happy to look into this further with you.
Just to note, that these taxes are related to your monthly subscription only, and are not influenced by the products or services you sell. So in terms of filing or remitting your own taxes, we would not do so on your behalf, but have some info on this here to help prepare and guide you through this.
I hope this helps - do feel free to let me know if you have any questions at all.