different stores in different countries need different taxs?

[yekstore]

Dear Friends!

I have a company registered in Canada and I have designed and prepared 4 stores to sell various products in
1- Germany in EU
2- Arab countries in the south of the Persian Gulf  in Asia
3- USA
4- Turkey
I have some good friends in each of the above countries, but I do not have a registered company in those countries and my company is registered in Canada.
Now I want to set the tax in my stores.
My question is, do I have to set a tax for Canada (where my company is registered)? or does each store have its own country tax?
Please give a full explanation.

thanks a lot