In France there are 2 large mobile operators: Orange and SFR. Tariff plans for them are approximately the same and expensive by Russian standards. On average, the minute of conversation with Russia will cost 3 EUR. The card itself with the number costs about 15 EUR and includes only 5 EUR for spending. To replenish the account you need to buy a card (there are denominations of +5 +10 +15 +20 euros) in a supermarket or a tobacco kiosk

For ten days it makes no sense to buy a mobile number card - you will spend a lot of time on this, and for money - little will be gained. It is better to use a payphone that can be found everywhere, international calling cards with detailed information on how to call can also be bought at tobacco stalls