I think as long as you don't exchange them into fiat ,you can't to pay taxes,but if you have to exchange them into fiat,then you have to pay taxes because the gov know your money!
this depend it's controversial, some government may track your bitcoin address to see if you are going to use them to purchase soemthing and avoid paying taxes
they can do this if you use some known exchange which have link with are controlled by your government, but anyway i doubt you can live 100% on bitcoin, and try this way to avoid taxes, not feasible for now
I’m not sure it would be that easy for a government to track bitcoin usage and whether or not people were trying to avoid taxes. I think it would be more work than the pay off they could potentially get my doing it too.
But, tax avoidance isn’t really why I at least and surely most people use Bitcoin so I don’t think regardless of the outcome that it really matters. A government needs taxes to run anyway.