Do you get taxed on crypto capital gains if you brought the crypto from overseas?

I'm basically an expat whose country of origin doesn't care about crypto or even have any laws regulating it, so I never declared my crypto or paid taxes on it in my home country ( Tunisia). I Recently moved to another country where capital gains on investments (including crypto ) are subject to 30% tax( France). Will I have to pay them even if my crypto comes from abroad, and some of it isn't even on exchanges? I'm still a student btw.

Also in case I do, should I just exchange all my crypto to usd if I want to minimize the taxes I will have to pay? (I'm in profit overall anyway, but still expect my protfolio value to rise more)