For roaming in France, check out Orange prepaid sim. There are other companies too. Start with Orange, that's the one I remember, searching for that will lead to other options. SIMS and plans are inexpensive in Europe. Better if your friend can buy a...
I have a subscription to NordVPN that I use mainly for my laptop when in public wifi areas. Occasionally I use the VPN on the cellphone if I'm on wifi in a public place however not if I'm connected to Public's data. I don't use any anti-virus or ad-b...