Which countries and currencies can I charge in?

Card payments go through your own Stripe account, so which countries work is Stripe's question rather than ours: your account has to be in a country Stripe supports for connected accounts, and your client can pay from anywhere Stripe accepts a card. Stripe keeps the current list on its own site, and it changes often enough that copying it here would go stale.

The currency is set on each delivery, from USD, EUR, GBP and JPY. That is what your client is charged in, so pick the one your invoice is written in.

What lands in your bank is a separate question, and it belongs to your Stripe account rather than to us. If the charge currency is not one your account settles in, Stripe converts it and takes its own conversion fee. Stripe's dashboard shows which currencies your account holds; if you invoice abroad often, that is the setting to look at.

If your country is not on it, the manual route works everywhere. Put an amount on the delivery, say how to pay in the payment note, and unlock it when the money arrives. A cross-border transfer is slower than a card and costs nothing here either way.