route specific traffics over VPN

Hello All,

I wanted to bypass censorship on YouTube and Facebook ,my internet is coming from a PPPoE connection so i created a l2tp/ipsec connection in order to route some blocked website through VPN. the problem is when i enable both PPPoE and VPN interfaces and select “add default route”, the default route for PPPoE in routing table becomes static not “dynamic active connected” and all traffic goes to VPN. I used mangle and NAT as you can see from attachments. please help me solve the problem in routing table which inactivates my pppoe when vpn adds default route and all traffics go through vpn only. if i do not enable add default route option in vpn it does connect but without any NAT. and when i use mangle to bypass blocked website it does not work and “waiting for website” is shown in chrome.
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