How much does it cost to send a letter to France?

I'm going to camp in two weeks and my brother's in France. I want to write him letters but I don't know how many stamps I'll have to put on. Can somebody tell me this, as we don't have access to the post office our letters will be going through at camp, and otherwise I'll be playing the guessing game.

us vpn

VPN is (Virtual Private Network) were first used by companies to enable their employees to securely access internal systems such as email remotely (e.g. from home or while on business trips). Today they are increasingly being used for personal use by individuals to protect their privacy while online in public places (e.g. when using the wi-fi connection in a cafe) or in a country where the internet is censored / blocked (e.g. China, Saudi Arabia…).