Where's the best location to set up my online store for tax benefits?

Hello Guys
Thank you for reading.

I am currently based in the UK and want to setup a Shopify online store. I am also a resident of multiple other countries like UAE and Cyprus and eligible to work there.

I am wondering where would be the best location to setup my business in order to pay the least taxes moving forward for my store, would I be able to change my business location later on even if I set it up in the UK ?

Also, I saw that the currency when someone accesses my store will be presented in the currency of my store’s location, shouldn’t that be relevant and adjusted to where the customer is accessing Shopify from ?

Some simple questions that make huge differences.

Looking forward to some insights