This vpns are based on my personal choice.1)ProtonVpn:
-Account needed but can create account using bitcoin payments
-Freemium
-No Logs
-Open Source2)Mullvaad
Huge Advantages:
-No logs
-Open Source
-Account needed but can create account anonymously using bitcoin payments.3)Ivpn
-No logs
-Open Source
-Runned by security experts
-Premium only
-US Based
-Can create account anonymously using bitcoin.4)Bitmask VPN:
-No logs
-Open Source
-Completely free (donations)
-Account can be created or can use it anonymously.
-US Based.5)Riseup VPN
Riseup VPN is a provider of bitmask
-No logs
-Open source
-Completely free
-Donation Based
-No account
-obfs4 proxy available
-US Based 
-Slow for me, i don't know what about you6)Calyx VPN
Calyx VPN too is a provider of bitmask.
-No logs
-Open Source
-No account needed
-Has obfs4(bridges) proxy 
-Donation Based
-Slow for me, i don't know about you.
-US Based7)Orbot
-No logs
-No account
-Donation Based
-Not a VPN but still secure.And, if you know any open source vpn then reply me:)