Possibilities for living

tax free.

50 - 50 plan

This is probably the most universal plan. Something everyone could do for a year or two as a working nomad. Or even just a nomad.

Basically if you live half the year in each of two countries and thus are non-resident in either of them you won't pay tax in either country. Your income will then only be taxed in the country where you earn it. For many types of income that can mean totally completely tax free.

For example bank interest in the Netherlands, UK rental income up to the personal tax limit for any commonwealth citizen or offshore interest income from a range of old fashioned tax havens.

Of course if it's a year or two travelling, a sort of extended round the world trip that you want there's no need to restrict yourself to two countries. As a long term plan, two countries is probably enough though with the odd vacation elsewhere so we will look mainly for combinations of two countries that could gel.

The countriy combination you can choose are almost limitless.
Winter in Thailand, summer in Spain?
Or Summer in Peru, hot rainy season in India?

Year Round Holiday plan

How about living in one country but keep most of your income and investments offshore?

Sort of like being on holiday year round. Only ever going back to the grimy place where all the work happens and your pennies are earned when you really have to.

For this type of plan you need a country where even if you are tax resident you are taxed only on the money you take into that country.
This is usually referred to as remitted income or remitances to the country.

Most European and developed countries as well as many South American and some Asian countries will charge you tax on your worldwide income as soon as you become resident.

Some countries which only tax remitted income for [some] residents are Singapore, Thailand.

If you live hand to mouth and always spend all the money you earn each year, this plan won't help you at all. It's only for those rich (or sensible?) enough to be earning much more than they need to spend and keeping a pile of dosh back to use for future yearxs. It might also be good if you use a large chunk of your income to support a family back home or even a charity in a 3rd country.