While Stremio doesn't share any data with your internet provider (ISP) they are able to see what you are doing in the internet. We don't control community add-ons, some of them provides torrent based sources therefore, before using them you should make sure that this is legal in your country.
We adhere following rule - "Only thing worse than no security, is a false sense of security". You should know that there is no VPN that will provide you full anonymity, help you with bandwidth throttling or protect against sophisticated censorship like Deep Packet Inspection(DPI).
VPN will help you to secure your connection and hide your internet activity from your ISP so they will not know nothing about your internet connection except the fact you connect to the VPN provider. You can read more information about VPN here.
We don't recommend any kind of VPN you should choose one by yourself. There are differences between providers so you should check which offer suits you well.